If money is no object - Kramer Horsehide Custom OW Belt Scabbard is super strong, light weight and IMHO the best I've come across to date! Will run about $125 or so. His design is built right and lasts almost forever so the need for straps, snaps, screws, velcro, springs are just not needed for retention and yet draw is excellent - I like that !!
The commercial holster makers offer off the shelf convenience, lower prices of course and they will fit the bill for short ocassional carry.
Since the gun you are asking about is so big and heavy I would think that a holster that will be used a lot should be the strongest and lightest as well as being the highest functioning holster I know of - which is Kramer Leather. His double thick Horsehide Belts are also TOP SHELF! After owning some of his Horsehide holsters for guns I cary very often, I'm done with Cowhide holsters - unless it is for Range only use, hunting or Cowboy Action events that just don't require the toughness and longevity of an every day use holster gets.