Hi, I've got a rear hope wheel with a SRAM driver, and want a Shimano one. Is anyone in the opposite position and want to swap free hub bodies?

What hub body do you have? I might have a freehub from a pro3 I could swap - not sure about freehub compatibility across the different hub models.

I ‘think’ the pro 3 and pro 4 free hubs are compatible (but not with pro 2 or pro 5)

Excellent question.... Think it's a pro4 but I'll double check when I'm home this afternoon