Looking at all three of my real Muasers, my Denixes, and my MGCs Boba's measurements are pretty much spot on.
I am using the real Mausers as a base for all my comparisons since the hero blasters were real. The Hoth, I'm letting everyone else worry about. I like the Luke so that's my focus.
Anyway, the Denix is larger than the MGC and real Mauser.
From base of mag well plate to lowest edge on upper receiver we get this:
Mauser: 2.222"
MGC: 2.285"
Denix: 2.337"
So to me boba's measurements work on a real Mauser. The 1.25" width of the base section MIGHT be a tad small... needing to be a little wider, especially for the Han Bespin, as they look slightly different, otherwise it's good. Say 1.35"?...
the rest checks out on real Mauser.
hoping more reference gets here soon
Alex, looking at your image up close I see:
Your top edge is too high up on the lower receiver... It shouldn't pass the bevel in the mag well as much, and also your plate goes too far down. Weirdly the protrusion on the mag well is exactly the same on real mauser vs denix (MGC is larger slightly), but on the denix it's more pronounced. 1.75" would put it about perfect when I measure. Since the denix is larger it would sit a tiny bit lower, but still be positioned about right.