RIA 12/6/19 auction realized prices on MAC family SMGs:
Powder Springs M10 .45 1972 low serial number w/RBP Suppressor $11,500
Powder Springs M10 ,45 1973 production $5750
RPB M10 9mm, no mag $5750
SWD M11/nine, faux suppressor, 5 mags $8625
SWD M11a1 Large magwell $6900