Soy Chunks - These are similar to Soy Curls, but they are in smaller chunks. You can use Soy Curls, but the Soy Chunks are way cheaper. Where I am in Southern California, they are ubiquitous in any Mexican / Latin American Market.
Substitute for Soy Chunks - You can also use some
TVP if you don't mind a smaller mince. Or you can do like I do in my
Tofu Taco Meat and just use crumbled Tofu and coat it in the Chorizo Marinade instead.
From 8 oz of the Dried Soy Chunks I used, I got a little over 1.5 lbs worth of "meat" once rehydrated, so as long as you have around the same in TVP or Tofu, it should work well!