Hi Terry
Unfortunately 1100RB footpeg rubbers are molded onto the footpeg and the footpegs are now unavailable. However it is possible to purchase some CX500 Turbo or CB1100F footpeg rubbers which can be fitted with a plate and bolted onto the RB footpeg, if you first remove the old rubber and drill the footpeg.
http://www.davidsilverspares.co.uk/CB1100FD-SUPER-SPORT-1983-EUROPEAN/part_52486/
Alternatively the CX500 Turbo footpegs will fit the RB mounting if you can find some at the breakers. I have these fitted to my RB and only a true R enthusiast would know the difference.