Aluminum Welding Flux?

[Gabe]

I am trying to weld aluminum with an oxyacetylene torch but am having a difficult time finding a source of aluminum welding flux.

My old welding books mention gas welding aluminum as long as a proper flux is used, but searches always find aluminum brazing flux (which I already have plenty of). With welding I can concentrate heat and lay a bead, but brazing uses too much heat and melts the base metal. Now I want to see how successful gas welding aluminum is, but I will need "aluminum welding flux" (I assume it exists?). I am hoping for advice from people with actual welding experience, but all comments are appreciated.