My thoughts would be something very similar to a "Banddolero" (Got no Picture). A pair of them, one with cartridges and shotgun shells, and one without would work well and get the guns back down to your waist. Still would recommend shorter barrel guns though, to ease the draw.
A Bandolier or Bandolero with the holster attached is not an approved SASS item. However, SASS and SASS affiliated shooting venues do make exceptions for physical impairment. So I'd suggest a visit with your local shooting venues and ask "May I??" then have the rigs made.
Stay Safe Out There
PS: The Skeleton rig as shown by Marshal Will Wingam would also serve quite well, with one on each side. The other solution is to stage your handguns but that requires a flat "table" on every stage.
PSS: JUST FOUND THE REFERENCE. It's called the "TUPELOBANDO" and it's made by Knightsleatherproducts. Taint cheap, but with a little modification . . . . . .