Seitan low carb high protenin veggie food, need vital wheat gluten

I am a long term veggie, and when visiting veggie friends in Australia, they served seitan escalopes which were really delicious.They are a tasty meat substitute, healthy and full of protein. I am trying to lose weight low carb so thought I should have a go at making it, even though it is a bit of a palaver. Once done it can be frozen.

The lady gave me the recipe which uses vital wheat gluten, I don't know where to buy it other than on line, just wondered (a long shot I know) if anyone else has made it?