ALDA screw destroyed housing threads!

[83mercedes]

When adjusting my ALDA set screw to make the mixture a little less rich--despite my efforts at being gentle--it popped up a little suddenly, ripping probably 70% of the upper threads out of the ALDA housing. Now, the only way I can get the screw in is to push it down and screw it into the bottom remaining threads (which causes the engine to not get enough fuel to go above 700rpms).
When I tried driving it with the screw out completely, the transmission shifts approximately 500rpms higher than it should, making it drive ridiculously and the fuel/air mixture is absurdly rich unless I floor it.

I can't drive it because I don't want to hurt the trannsmission, and it is pretty embarassing, so does anyone know where/if I could get just the ALDA housing? I'm afraid the magnitude of this problem may be horrific. I can't just have a machine shop rethread it, because then the screw would no longer fit.