Seems this topic keeps popping up so I thought you would like to see this solution. Sella Regal Gilardi is easy to do and though this shows a fabric material you could use leather quite easily original rivets are drilled from backside (be careful as you need to use the upper portion again) washers are backup washers for 1/8 rivets but you could use a #6 flat washer. Cover is glued at front ,stapled at sides and riveted at rear. You could probably glue at sides using Leather but stapling fabric seemed better than glue.These saddles have light padding but you could use neoprene (available from Dive shops) to build up padding to level that you like. I used 1/8 x 3/16 rivets and probably could have used 1/4 grip instead (measure hollow part of old rivet to see how deep you can go). Its quite simple to re rivet the old rivets thus retaining the classic look. Availability of leather colors is almost limitless (try craft supply or look up 'shoe findings' or leather supply in the phone book.)
BOB FREITAS
MILL VALLEY, CA USA