Have joined the UK and US users group and posted there for the brackets and the rear taillight/indicator unit. Here's hoping of the best. I wouldnt have thought the parts would be that hard to find. It seems as though the RH was a limited release and theres not many around or they are not being parted out. Theres alot available just not for the RH specificially.
The RH (5N5) is a variant of the European "S" (5K7). There are VERY few RH parts with 5N5 part numbers, but shed-loads with 5K7 numbers... If you're looking for spares in the EU or UK, try spec'ing 5K7...
5N5 parts that I know of..?:The side reflector brackets and reflectors fitted to the sides of the oil-cooler.
The indicator lenses (although Christ knows why 'cos I have a set of RH indicators in the garage and they're 100% identical to the S ones...)
The front mudguard (has threaded holes for a front Reg Plate. (They'd been banned in the EU/UK by 1981...)
The stay that bolts to the front guard, to hold on the Reg plate..
The tail-light assembly... (It's a 5K7 (black chrome) jobbie with a different lens - No side reflectors for EU/UK versions...)
Other than that, the 5N5 is the same as the 5K7... Even has a 5K7 frame part number...
Hope that helps
Miti