Rear Brake Master Cyl

Does anyone know if there are two types of rear master cyl for the FE?

I’ve just bought a kit that is for mine but it doesn’t fit, mine has a piston with two rubber seals and this kit just has one (similar to clutch and front brake)

Kits for the R model seem to look like the one I have so I wonder if someone has slipped an R master cyl on??

for future reference always strip the part and confirm the replacement parts are the same visually.
My vf had loads of vf750 parts on it when I got it so I got more than confused with the rebuild