For Trade My Olympus OM Zuiko 50mm f1.8, 28mm f3.5 for your ?

I have a nice 50/1.8 Zuiko (F. Zuiko, nice and sharp) and a 28/3.5, both with very nice glass, overall excellent condition. I'm interested in trades for similar condition glass (or something else?) for the following brands:
Pentax screwmount
Minolta MC or MD
Canon

If you want to trade (or would like to buy outright) please shoot me a pm.

I'm in California.