I usually use a different powder for the type of loads you are looking for. I use SR4756 under a 160+gr LSWC with White Label BAC lube for 1250fps from a 6" M586. The load is outside of current data so I won't post it on the open forum, sorry.
What kind of recipes do you have for the powders you listed?
Have you tried Hodgon's data website? They should have data for the powders you are looking for.
I don't shoot a 125gr bullet out of a 357Mag handgun much at all. Making the different weight bullets have the same POI is going to be difficult and trial and error at best. Dwell time, recoil and all.
Sounds like you have a project on your hands!
Fun stuff!