A good few years ago,I needed a front screen for my '62 Olds after some tosser threw a brick through it.I think the company I used was called American Auto Glass.It wasn't cheap but,they drove up to Scotland and fitted the new one at my front door.Great service.
Also worth checking to see if your screen is interchangeable with any other GM models.I think mine was the same as '60 or '61 Chevy.Might make the search a little easier if you don't want to pay out for a new one.
Mark.