CAUTION: The following post includes loading data beyond or not covered by currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assumes any liability for any damage or injury resulting from the use of this information.
Sounds like you need a 300WM / .17 HMR over/under.
I think a lot of what you want to know about .45 Super except load data
is in, believe it or not, the Wikipedia.
It is basically identical to .45 Auto but tweaked to withstand 28,000 psi. This is done by thickening the brass on the inside to reinforce the head, and by restricting the round to use in barrels that supply full case support. A stiffer recoil spring is also used with them in that pistol. For your Glock, you will probably want to look at an aftermarket barrel with good case support. I know Storm Lake makes some. I would call and ask them or another barrel maker about the barrel choice. The outside dimensions match the standard .45 Auto round and, as already mentioned, it uses the same bullets.
As far as the loads go, it should withstand charges about 9% higher than 45 Auto +P loads. It varies by powder, but QuickLOAD is a good way to tell the percentage-wise change. It was 10% with Bullseye and 8.9% with Power Pistol in the loads I tried.