Try emailing them smgguns@yahoo.com and ask. Mine was using a kit from RTG that came with a good barrel and they welded my cut receiver back up, added their semi mods came to $2500. Not cheap but IMO the SMG's are the best known DP28/DPM builds of this type and run very well. Lots of YT vids of them with no issues.
I was told mine is close to being done and ill post it here when I get it.
Thinking next of having SMG build me an FG42 next if their DPM is as good as folks say.
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