Stuck Aperture Blades, Rokkor-PF 135 2.8

Found a 135mm 2.8 Rokkor FD for $40 with the "like new" description online, couldn't resist and bought it. Now that it's in my hands it had dust all over the front and rear element but I cleaned it really nice, no scratches anywhere.

The bigger problem is the aperture blades won't move, it's stuck wide open. So before I send it back I wanted to know if there's an easy fix, if anyone has some experience with this kind of stuff or this lens. I took it apart but honestly I'm not sure what I was looking at, I didn't see anything that looked out of place so I put it back together.

Help?

--
-Dan