Gunsmith in Bay Area

[408ready]

[recpark99]

Depending on how deep it is from the top of the sight, you might have to sacrifice the sight to get it out. You may be able to Dremel a slot in it to get a flathead screwdriver to grab it. Might try Ryan at Sagisi Customs at metal dog tactical

[67Cuda]

Easy out or left hand drill. At the very least, pop the head of the screw and take off the sight to expose remaining threads.

I wouldn't try it without being able to set it up on a mill.

[divingin]

Allen head will guide the drill bit pretty well. Drill until the head releases from the screw shank, remove the sight, and you may be able to grab the exposed screw to extract it. Hopefully you didn't Loctite it.

[dk94044]

Try using a thick wide rubber band under the bit for more bite, push down hard and twist very slow

[kendog4570]

[DrJeds44]

Coyote Point Armory in Burlingame can take care of you.