[RPG] What’s the price, weight, and capacity of a Large creature’s gear

Unfortunately, no explicit rules for the purchasing of normal scabbards, lead lined or otherwise, are given, at least in the SRD. Nonetheless, we can get a fairly precise answer.

An ounce of lead is a costless focus component for the spell Lead Plating found in Kobolds of Golarion. This means that lead is effectively free, at least in the quantities you need to line a scabbard. That just leaves the cost of labor if you aren't willing to do the lining yourself. At this point we have to determine whether a lead-lined scabbard requires a scabbard and lead as raw materials (in which case it costs twice as much as a scabbard does) or whether it requires a scabbard's raw materials (i.e. half a scabbard, in which case the cost is no different than a regular scabbard) to complete.

Assuming you use a normal scabbard, things are still complicated. Scabbards appear to be either free, or possibly included as part of your clothing/weapon/something else, which puts the cost into GM discretion up to twice the cost of the clothes or weapon the scabbard came with.

If your GM is charging you some incredibly unreasonable price for a regular lead-lined scabbard, buy a lead-lined combat scabbard instead, which costs a maximum of 2gp (assuming it's not sharp. Sharp ones go up to 20 gp in the worst case scenario).

If you happen to be playing with the 3rd party Pure Steam Campaign Setting, there are much more explicit rules for lead lining stuff and it is, indeed, free.

If you are the GM, the price should be no different than a normal scabbard, and thus free if you don't track equipment very closely and less than a silver piece but more than a copper piece if you do.

There is no simple (official to my knowledge) answer.

When magic is involved the cost is given by the magic enhancement irregardless of size. As money quickly goes into the tens of thousands, few care about tiny sized weapons base cost instead paying full price and saving time on the paperwork shortcut.

However, there are some suggestions:

• DMG has section about modifying equipment for abnormal body types, such as wings or extra arms. Its 30% more base cost. Considering the difficulty in making tiny rivets and stitching...
• Model the solution off of armor: Tiny, Fine, & Diminutive = 1/2 x Small. Large x 8 = Huge x 4 = Gargantuan x 2 = Colossal (doubles each size increment). The larger options being for material costs, while smaller requires crafting skill regardless of material savings.
• Outside of weapons: magic items (like rings) adjust to user size and have the same cost and weight. Personal items (like tents, food, water skins) adjust by 3/4th per size increment by Player Hand Book. Some items (like tools, vials, books, and rope) have a fixed cost regardless of character size, by logic and player hand book. [Huge troll climbing thin silk rope, maybe house rule that?]
• In general, the answer is always ask the DM, house rules abound. Some campaigns ignore weight in all but extreme cases. [Carrying a castle or 100 weapons.]