It's probably not the screw that's stripped. The screw threads into the other half of the keyfob and it's the plastic that's stripped. I suppose you can fill the small hole with a drip of epoxy and then re-thread it. Or, you could carefully heat the plastic and squeeze the hole to deform it, then re-thread the screw. But, it's so small that the heat would melt the surrounding area.
FWIW, I bought a pair of housings from Amazon for very little - maybe $10 or so - and while they aren't OE quality or feel, they work. Mine were failed in the same way - the plastic was damaged which prevented the screw from securing the two halves.
The microswitch that controls the lock circuit broke on one of my fobs; otherwise, it works fine. Are you saying that these switches are available somewhere or did you buy a fob and desolder one of the switches to put on your programmed fob?
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