Preferred tequila age for Strawberries Por Mi Amante

The tequila probably plays two roles in the recipe: as flavor and as a solvent. The alcohol in the tequila will dissolve certain components in spices that water or oil do not. On the flavor side, tequila is basically a floral smell, so (and sniff together before you say no) why not try rose essence and honey with maybe a tiny bit of some cinnamon. You can find cooking rose water in ethnic food stores. It is used in Persian and Indian cooking.

Decent port is not necessarily expensive; you may find yourself spending more on the meat. For example, Sandeman's Founders Reserve 750 ml runs about US$15 before taxes, Dow's Fine Tawny 750 ml is about US$13, and Graham's Six Grapes Ruby 750 ml is about US$8 (and this is just the start of the list). These are, perhaps, not the connoisseur's choices, but they are hardly undrinkable. Depending on the laws where you live, you (or your favorite wine shop) can order any of these online from a variety of sources.

Port has a unique character that is not easy to replicate with any other wine or fortified wine. If you are trying to replicate a result, do not substitute. If you really want something else that will serve the same role even if it will taste different, I would look to a Madeira, a cream sherry, or sweet Marsala (depending on your tastes).