I used Power Brake Booster of Oregon, the guy that runs it calls himself "Booster Dewey"
Great guy to talk to, great product, definatly where I would go again.
He stocks the single pancake boosters, but does not rebuild the later tandem boosters unless you ship him a Toyota kit with it. (He says that his kit supplier has a crappy kit for that booster and it is not worth rebuilding it with it)
I used Booster Dewey as well for my Tandam booster. Cruiserdan got me the rebuild kit which I sent with the old booster to Power Brake of Oregon. It all turned out great-as good as new. I would do the same again.
I've taken apart my break booster before ( early pankcake model) and it's not complicated. I've often wondered why people don't rebuild them. Did I miss something? I'm the first to admit I'm ignorant and haven't rebuilt one. Why would one not buy a booster kit from cruiserdan and do it solo?