I'd go with either DD or BCM, they're both fully milspec. LMT is good but make sure you get their M16 carrier not AR-15 style. Colt is excellent too but about $180. I'm not sure about Spikes... I went with DD last year and have been pleased. The one I got had the unmarked carrier but the current ones tend to have the DD logo on the carrier. BCM of course has a pretty conspicuous logo on theirs if that matters to you.
Hope quality parts catch up to demand again, a shame so much is hard to find lately.