The M2HB is often referred to as 'Ma Deuce' - but thats a .50 beltfed. Very similar design to the 1919 though (both by J.M. Browning). The 1919 can be chambered in .308, 8mm, or '06. (The Israelis used them in 308, the US is '06, and 8mm conversions have been recently made by a number of commercial manufacturers to take advantage of cheap 8mm ammo). If they said it was a 1919 and in 308, my guess would be a side-by-side mount like the one pictured, although the barrel length may (or may not) be longer.