I can't speak to the UG provenance.
Make sure it is not 30mm if you are expecting bigger!
Price seems OK for a punt,
but as with any vintage, you should be prepared to put some more $$ into future servicing.
Is it normal to have that gap around the movement?
Modern pieces have a movement holder ring.
See if you can figure out if the crown is original,
my guess it is that it is ... but often this is something that gets swapped out on vintage.
The dial imperfections have to appeal to you, but they are at least evenly distributed.
As you will have noticed, it seems to have a personalized inscription... as long as you are cool with that.
I can't make out all of it, but seems to read something like "Jean Baughs, Brigadier, 196X - 19XX"
Many vintage are plated cases, gold, chrome, whatever... this case looks pretty good whatever it is.
Hands, indices and dial text seem in good nick, but not suspiciously good.
Good luck!