Have done this plenty of times on virtually all of my Mosrites. I will take a try at explaining this without the benefit of graphics.

You need to use liquid wrench, instead of lube oils like WD-40. Put on the liquid wrench and try to rotate the rollers - use a thick twine going over the rollers, pull down the twine on both sides to put pressure on the roller - just like the strings and go back and forth to move the roller. The liquid wrench takes the rust out; once the rollers are free, use a lube (WD40 is good here; being old fashioned, I use 3-in-1 oil) and paper towel any excess out. Excess oil tend to attract dust and grime. For real stubborn rollers that are stuck, here's Plan B: Take the bullets out and use a small nail as a punch to drive the rod holding the roller out of the bullet. (You need to do this carefully - I position the bullet on a table vise, with the jaws slightly open, with a soft cloth covering the gap and put the bullet lengthwise parallel to the length of the small gap. You need to use a sharp tap to get the rod out; if you use repeated tapping, the rod will not stay in the bullet after reassembly.) Once the roller is out, use fine grained sandpaper to smooth the flat sides of the rollers and the sides of the bullet that are in contact with the flat surfaces of the roller. Reverse the disassembly process and put everything back, after lubing the roller holes on the sides of the bullet. After this treatment, my whammies behave perfectly and stay in tune for a long, long time (I mean days) even after VERY hard use.
Scot - this is for you, since you are in IA. Many, many moons ago, just before I graduated from Iowa State, I thought that I was the only Mosrite owner in Ames. (I had a 66 V's model - my first Mosrite ever, bought from Buffalo, with me at that time.) To my surprise, I discovered a 64 V's model in store in downtown Ames (at one end of Main St.). The owner (Terry) would not sell it - you may be able to persuade him to do otherwise, restore it to a decent shape and luck out!
As for me, I am on the east coast and have not gone back to Ames since I graduated. If I remember it right, you are about 2 hrs away from Ames, so this may be doable for you.
-Kanad