Tomb of Annihilation and Storm King's Thunder are definite outliers in regards to the guidance from Xanathar's guide (both of these are excellent books, and I'm going to try to avoid giving significant spoilers).
In ToA, if you only consider items found in treasure blocks in the book, the party would have to stumble into every encounter with magic item rewards on their way through the jungles of Chult in order to come even close by the time they reach Omu (by which time they're supposed to be about 5th level). The tomb itself has a higher concentration of magic items, but 9 of them aren't supposed to be able to be removed from the tomb and most of the remainder are cursed (2 can actually kill a character who uses them with high probability).
Storm King's Thunder leans in the other direction. It's not at all uncommon for parties to be "overburdened" with magic items by the time they're done with the book (around level 10), having more magic items which require attunement than they can attune to, and several besides. For example, one quest awards a minor magic item (of their choice off a list) to every member of the party around level 5.
Yes, if you have fangs.
You've already rightly pointed out that you have "appropriate fangs", but I wanted to expound of this a little bit to make sure future askers of this similar question understand that caveat. You need fangs to make the bonus action unarmed strike.
While shifted, you can use your elongated fangs to make an unarmed strike as a bonus action. If you hit with your fangs, you can deal piercing damage equal to 1d6 + your Strength modifier, instead of the bludgeoning damage normal for an unarmed strike. (Wayfinder's Guide to Eberron, p66)
Many longtooth shifters have canine traits that become more pronounced as they shift, but they might instead draw on tigers, hyenas, or other predators.
And then
You retain the benefit of any features from your class, race, or other source and can use them if the new form is physically capable of doing so (PHB p67)
So, yes, you CAN make an unarmed strike in wild-shape, as pointed out in this answer. But here's the catch: you don't have elongated fangs unless you assume a form that has elongated fangs. Wildshape limits your racial features if your new physical form is not capable of doing so. Furthermore, you adopt a new physical form, so you wouldn't have your previously elongated fangs, you would have new teeth. If you transform into a horse, you don't have elongated fangs.
So what this means is that you can't use your bonus action to make an unarmed strike because you don't have the prerequisite (using your elongated fangs). And even if you could, you wouldn't get the elongated fang damage because you also didn't hit "With your fangs".
But lets say you DO have fangs, like the aforementioned tiger. Then you absolutely could make that unarmed strike with fang damage, provided you were Shifted before you made the attack.
What are "Elongated Fangs"?
The "Elongated" fangs are relative to your humanoid form.
Many longtooth shifters have canine traits that become more pronounced as they shift.
So you have sharp canines as a humanoid, but they can't really bite things that well. When you shift, they are elongated. So as long as your new form has fangs, like most predators do, then you can use them. Don't think of elongated fangs as these huge dagger-like, snake-like fangs, but rather just elogated in relation to your humanoid canines (which are already pronounced). A tiger, for example, would have fangs that are elongated in relation to your humanoid fangs. Your DM will decide if your fangs are good enough to use, since the rules don't tell us which animals have fangs nor how long they need to be. We have to use our best judgement.
Best Answer
Wayfinder's Guide to Eberron p. 46 has a section on "Creating Magic Items" with rules adapted from Xanathar's Guide to Everything and prices aligned with its "Buying a Magic Item" downtime activity. It suggests that House Cannith would be able to make many items at a much lower price, but common items look like they would be fairly priced at around 50 gp (probably more).
Xanathar's Guide to Everything p. 126 has the "Buying a Magic Item" downtime activity which is as far as I know the only way to buy magic items by RAW. The asking price for a Common magic item is listed as (1d6+1) x 10 gp, or half of that for a single-use item like a potion or a scroll. This isn't counting the 100 gp and one workweek of downtime spent finding a seller.
Normally there wouldn't be any guarantee that the particular item you're looking for will be for sale. To find a particular Common magic item your Charisma (Persuasion) check needs to beat a DC 10, with a +1 bonus for each additional workweek or 100 gp spent searching (up to a maximum bonus of +10). However, because Eberron is a high magic campaign XGtE suggests adding a +10 bonus to the check result which would mean that you can automatically find any given common magic item for sale.