My experience has been that they're pretty hard to come by in the used market - people tend to hold on to them. They're a high quality revolver, light in weight and a lot of fun. When I was younger, I used to see them with trigger shoes installed, which I was always cautioneed that it was an accident waiting to happen. Now that I have one, I understand why others have equipped theirs with a trigger shoe. A combination of a narrow, serrated trigger, and a small grip frame makes it no fun to shoot in the double-action mode. Currently, I'm looking for a smooth faced, wider trigger for my Model 34-1. If I can't find one, I guess I'll find a replacement trigger and polish the serrations off of it to see if that makes a difference. As you probably know, the Model 63 is the stainless steel version of the Model 34, and they are just as difficult to find in the used format. I agree with sqhead's assessment - around $500.00 - $600.00 is the going rate for either a Model 34 or Model 63 - assuming you can find one for sale.
Best of luck,
Dave