If I come across phone numbers, I'll let you know. I have a couple books somewhere too. But here is the place where we got white gas, and they had equipment there. As well, there were other equipment shops nearby there too. It was in the center area of Mendoza.
It was called El Refugio. Sale and Rent Aconcagua Equipment. Address was 290 something. I got that off the picture I took!
Good luck. Mountain John