Where Can I Buy These Ingredients?

First, call your local co-op or health foods store.  They will likely have a some of them and maybe all of them.  Here are some of the places where you can purchase these ingredients online.   

Soy Protein Isolate

This is a common product at health food stores, co-ops and also bodybuilding health and vitamin stores.  The key is to check the ingredients.  You want Soy Protein Isolate 90% or as close to 90% as you can get.  90% seems to be the standard to be called soy protein isolate.  Don't buy soy shake mixes.  You want the pure stuff.

Amazon.com

iHerb.com 

Luckyvitamin.com

Genutine

This is a custom product that is only available from 

Le Sanctuaire.

One pound of Genutine will make 32 batches of marshmallows!  Woo hoo!  It works great but if you want to try and recreate it yourself, it will be much more expensive.  If you want to give it a shot, here is my best guess at the Genutine mix.

Guar Gum

Barry Farms at Amazon.com

Locust Bean Gum

L'Epicerie

Xanthan Gum

Barry Farms at Amazon.com

Acacia Gum, also called Arabic Gum or Gum Arabica

Amazon.com

Carrageenan (Kappa, not Iota) 

Kappa is used for stronger gels.  Iota is used for softer gels.  You want Kappa.

L'Epicerie

Le Sanctuaire