I have subbed the tomato powder with chicken bouillon with tomato and it was good but not as good as tomato powder. That being said, tomato powder is expensive (amazon) and only sizes are enough to make this recipe 100x over.
One thing I tried was the chicken/tomato buillion and a little tomato paste.
Tomato paste is shelf stable and cheap. Play with the amount at home until you get taste/consistency you like.
Either way this is one of my favorite recipes and goes over big with my camping buddies every time.
I also sub out andouille sausage for the summer sausage. Have also tried jerky but doesnt taste the same.
Good luck!

We haven’t tried that substitute, but I can’t imagine it would be bad. It will lose that bright tomato flavor and skewer more savory. Sort of a different flavor, but probably still good. Let us know how it works out.

Doubling everything seems like a good place to start. But, if you’re going to make this for a thru-hike, we HIGHLY recommend you make it at home first. Depending on the spices you pick up and the type of modifications you make to scale it up, you will want to be 100% on the recipe before you pack it out into wild.