SFIC bases are definitely my favorites for most MP purposes, I think they are as clean and have as few additives as you can get in non-home made MP bases. I am in CA, so shipping is probably cheaper to me than it would be to you from either BB or Wisteria Lane. I have been making less MP, but when I did more of it I ordered it in 50 lb logs, which cost @$115 plus shipping from WL. It was cheaper that way, and WL makes the extra hard clear MP base, which I don't think BB does, and which I prefer.
Not sure who else carries SFIC in smaller amounts, those are the only ones I found. Did not realize BA's base was SFIC, I would definitely check the ingredients on all the ones I am looking at to make sure, as well. Here is the list from WL's extra hard clear, the one I usually use:
Saponified Vegetable oils-primarily Coconut Oil
Glycerine (kosher, of vegetable origin)
Purified Water
Sorbitol (from berries, moisturizer)
Sorbitan oleate (emulsifier)
Oat protein (gluten free conditioner)
ETA: WL lists all the ingredients in their bases, on each one, I think. Anyway, easy to find on their site. You might want to just find the base you think you like and google the list of ingredients to find the match from other potential suppliers who are closer.