M1A/M14 bolt drawing number question

[Shear_stress]

Looking at a standard M1A, serial number 87xxx, manufactured in the mid-90s. It's got an H&R barrel, and some other USGI parts. The bolt is marked as follows:

00 87799
9810844

I believe commercial Springfield Armory bolts are marked "7790186-SA", which leads me to believe that the bolt I'm looking it is USGI. Does anyone know who made it?

 

[Match14]

I have an TRW and Winchester bolt, so I can say with certainty it isn't either of those. I'd try posting the question here.
www.m14tfl.com

Of course you'll need to register though.