Sorry for the delay in getting back to you but I wanted to get them into the UK and fitted to the Roadster to make sure everything was OK before letting you all aware of the supplier.
Contact;
www.speedwaymotors.com in the USA and put into their search box 910-13011-2.125-raw and it will take you to the stainless steel U clamps 2-1/8" for the Morgan, in the States they are called Muffler Clamps.
I hope this helps