I have a brand new set of powerflex front control arm bushings for sale.
These are the offset version
to add castor like the E30 M3 was setup from the factory. I bought them cause they are a FAR better design than the normal poly inserts but it is that design that is making them not work in my odd application of E46 control arms on an E30 chassis.
I bought them last week and my loss is your gain. It's a long shot but I would trade + cash for some treehouse style ones if you have them.
Pickup in Toronto or Collingwood
You can see photos of them at these two links.