John,
I'm certainly not an interior expert, but I did replace mine last year. I checked many sources and ended up with Ron Rabon at Ron's Restorations. In fact I just sent a door panel back to Ron for some fine tuning. I've found his pricing to be fair and the real kicker for me was that I could pick up the phone and talk to Ron directly. Simple things like, walking me through which pieces to put back on the car first was a big help. He has a small personal shop which I found refreshing compared to some of the big boys. I shipped all my pieces, including the seats to Ron and he recovered and sent them back. It all worked well. I have a cognac interior. I've discovered that one man's cognac does not another make. They all have different graining in the leather (blaming the cow, not the supplier) and the dye process can be very different supplier to supplier. (no fault of the cow!) Ron sent me several swatches so I could find exactly the cow and the dye I wanted. I don't think he would 'steer' you wrong!:)
Anyway, I think it's worth your nickle.
Tim Dunagan
1971 280 SL