Hey all!
New to the community, and I’ve managed to stumble upon what I believe is a GE M250A. Inside there’s a tag for a 175W 240V Mercury Vapor ballast/fixture, date code is (ironically) GE which means it’s from 4/1969. But it came without a refractor, only shards of glass rained down on me once I opened it. Attached is what I’ve got. My questions are: Is this a M250A, and where could I get a new refractor?

I don't know much about these, but maybe you might find one on eBay. Also this site might have some, I don't know them but I see it says they have some for M250 models if that's what you have.

http://z-mods.com/forsale.html

Yep that's a M-250A! The link Cole linked is to my friend Steve's site. He should have the proper glass for your light. Just ask for a "Deep M-250 glass".