I'd say somewhere in the $400 range would be fair. Through a dealer in '95 or so my first .223 NHM90 went over $75 more than the 7.62x39 version or MAK90's were going for.The NHM series rifle, unlike most* MAK90's were indeed pre-ban guns modified to comply with the provisions of the '89 ban. (* As were the earliest MAK's)
Good guns, I have a pair of them now. Things to note:
1. Magazines are kinda pricy (30 rounders average $30) (5's, 10's, and 15's are usually $15-$20 each)(There are 40's out there, expect to feel raped upon purchase, they are extremely "Kool!" though...)
2.Replacement bolts are a tricky proposition,thanks to Klinton's ban on Chinese replacement parts importation. (Too bad some european nation didn't order 10's of thousands of 84s rifles and mags!) Everything else can be replaced with 7.62x39 parts, both Chinese and some Euro AK47 parts (not AKM parts though)
3. If the rifle hasn't been altered, there should be a 2" long piece of pipe welded to the muzzle. It is both welded and threaded on, meaning the original 14x1LH ahnd threads are intact underneath! Any 14x1 threaded muzzle brake you prefer can easily be swapped, it should be welded in place to be compliant with current legislation...(Same applies to adding pre-ban style stock sets--gotta watch your parts count...)
4. Rate of twist is 1 in 10
I love mine! Plenty accurate for a Kalishnikov design. I've never bothered to line 'em up with 5.45's for side-by-side comparison but they outshoot my 7.62's. My best results have been with 55gr.fmj.I've had fantastic results with (remanufactured) 3-D Coytee varmint ammo loaded with Hornady V-Max bullets. Wolf ammo, not particularly noted for accuracy shoots well through mine and is plenty cost effective as "blasting ammo".