I have the same question, only for a 9.5" barrel (with or without scope).
How about these guys?
http://www.cowboyneeds.com/holsters_for_ruger_redhawk-9.5.html
I've seen other shops selling super redhawk holsters, but all the images they show are for a "non-super" redhawk (no extended frame), so I was skeptical.
Needs to be left-hip cross draw as well.
-edfardos