Glock 20 Gen4.  I use the stock barrel for light loads and a KKM 6" for heavy loads. 

6" barrel:  180 gr XTP, 9.1 Longshot average FPS of 1,357.

The 10mm started to really gain in popularity about 1-2 years ago and there weren't a lot of gun manufactures then.  There just aren't a lot of accessories unless you are shooting a Glock. 

Maybe Lone Wolf www.lonewolfdist.com , but i can't say for sure because i only look at the Glock accessories.   You can also try the usuals like Natchez, Buds Gun Shop, Midway USA, etc.  Your best bet is to just type in exactly what you are looking for in a google search.