I have an IPD rear swaybar for P1 cars (S40, V50, C30).
I believe it is compatible with cars that have the vertical or horizontal end links, I think there is more info about that on IPD's listing for it.
Located in Canberra but I can post it.
Asking $250 ono. It costs $280usd to get new from ipd which is about $370aud before you even add postage from the US.