I'm still trying to figure it out as well. I think for flour, experimenting with any artisan bread type flours would be good. The wheat flour at your supermarket may work though, you'll likely need to try it out and compare. The differences can start to become subtle. Vegetable shortening is also a decent replacement for lard, the ones like Crisco that come in a can and look like lard/non liquid oil. Some of my favorite taco places like https://www.instagram.com/elrusola/ use exclusively that.

I would also avoid things like Maseca if you have the time to try to figure things out, since they are a pre mix just add water type thing for corn tortillas specifically.

Maseca. It's the same as they use in Mexico, and happens to be produced in Italy.

Get it at your local delicatessen, or your local Hyper Market.