It is likely something you can do yourself, but you may have to take apart the wind knob. My IIIf had a screw on the knob loosen, and become jammed inside. Rendering it useless. After poking around on RFF, and the web, I found a copy of the IIIf service manual that allowed me to carefully take the wind side apart, and put it back together correctly without sending it off.
As I recall, there is a little bent washer that holds the counter against the gearing. When I first got mine back together it was a bit loose because I'd cleaned the grime off. I had to give mine slightly more bend to get it to work properly.
Most of the things I tinker with are useless to begin with, so this slight "operation" made me sweat bullets, but it went smoothly with the manual as a guide. And it really is only a guide, there aren't step by step instructions.
Best of luck!