To go on an Alice belt you may want to look at the Bianchi MH05. They are ambidextrous and compatible with the military M1425 drop leg extender and UM84H shoulder harness. The mounting system is top notch and works with any belt. Since they are recently discontinued models they can still be found, and at very good prices. You can also get the matching Bianchi 1025 or 1030, 2 or 4 magazine pouches with the same mounting hardware as the holster that will fit your Alice rig and the M1425 drop leg extender.
MH05 Military Tactical Holster
If I had a light on my pistol I would have gone with one, I went with the Bianchi M12 for my Alice rig, and am searching for a bargain priced Bianchi UM84R (the M12 for a revolver) for the other side.
Bianchi M-12 and M&P45