Dommi 88 Swept Back Exhausts.

Armours supplied the same pipes for the 88 and 99  although the fit would not be quite the same for both  as the height was different.  The 88/99 ports are a shallower angle than the 650  so need different pipes.

Speak to them on the phone rather than order on a website site. The angles of the pipes out of the head changed. The 99's all had the earlier angles and the 650 and most 88SS have the wider splayed pipes. They'll know what you need.

Firms have to have websites but they are almost impossible to get everything right...

I bought these swept backs for my Dommie Racer, using a 1959 88 engine.

They are available from RGM and I have no issue with them.  Engine runs GR8.