The rifle is a full factory Eagle Arms EA-15 carbine and has given me 10years/~5,000 rds.  of very enjoyable and trouble-free service.
Looks as though now is the time (finally!) for replacing parts - which I'm glad to do.

At the last shooting session I had chronic failures to eject, so I figured it was the extractor/spring or the ejector/spring. At disassembly, sure enough, the ejector spring was in three pieces and preventing full forward tension on the ejector to fling the case out effectively.

Easy fix, but I also noticed a hairline crack on the bolt located at the cam pin hole. The crack runs 180 degrees across from hole to opposing hole, therefore splitting the bolt halfway.
That, I did not expect to see.
So, out the bolt goes and I'm shopping for a new bolt.

Q - Where's a good online place/price to get a mil-spec quality complete bolt assembly? Fast service would be a plus.

Q - I'm under  the assumption that (of course) the new bolt assy. must be head spaced right?

Denny's Guns
Bravo Company
LMT
Complete bolt carrier group 120-160, can go into the 200 range for some BCGs

All very good.

Headspace is a touchy subject, some say you must, others say you don't. Since this is a public board, I recommend that you headspace anytime you change the bolt, bolt carrier group, barrel or upper receiver. After all, what's the worst that can happen if you check it?

Thanks....
So would it be better to just replace the whole BCG and not just the bolt?
I get the feeling that a new bolt in a used carrier is a no-no - or just not preferable?

I looked at Denny's website and like his super duty BCG from CMT components.
I want these parts to be as tough as can be had so I don't mind spending a few extra bucks...
There are 2 choices on Denny's handbuilt BCGs: AR15 and M16. What's the prime reason for wanting M16 in a semi?

Quoted: So would it be better to just replace the whole BCG and not just the bolt?

If you have the funds to replace the entire bolt and carrier, then by all means do so. But, you would be fine just replacing the bolt itself.

really no difference on a semi as a M16 has more mass. On a carbine this might be an issue, but i never had any problems.

What you want is a carrier that has the firing pin projected.

Denny has the best looking bolts! Quality parts for sure

what about hard chrome bolts? any downsides to recommending him one of these ?