In search of a valve spring retainer

Hey guys, I'm in need of some knowledge superior to mine. I just purchased my first jeep, 77 cj5 with 304 v8, and it was smoking severely when I got it. Tore the motor down for a rebuild and everything is going good until the machine shop called and said there is a valve retainer broken and they can't find one. I've searched high and low and am having trouble finding one myself. If there is anyone out there with a spare retainer laying around I would be more than willing to pay for the shipping plus what ever you wanted for the retainer. If not, does anybody know of an aftermarket retainer that will fit on the spring and keeper and still keep the correct installed height. I know that edelbrocks won't, they wont fit my springs.

Thanks,
Jerry

In search of a valve spring retainer