I had an F2 that did the same exact thing. Having been taken out to dry AND treated rudely and, let's call a horse a horse, lied to by camera repair persons, I went the easy and sensible route. Sold that one and bought another one. It wasn't that long ago that KEH had reasonable prices and stood behind their warranties. Those times are long gone though, at least on prices.
I think like the op, a lot of Japan sellers have done an excellent job of manipulating the used camera/lens prices into the stratosphere. It's called price fixing and collusion. This didn't just happen by accident. Of course, there are surely those that are honest, but how can you tell? You better read their descriptions closely. Often they rate a camera as Exc, only to later say that the shutter doesn't work or something. It's worse on the lenses. What do you do if the camera breaks or isn't as advertised? Ever price sending a camera to Japan from the US? You'll pay for shipping it back to you too. If you like the F2, I would just replace it and save yourself a lot of risk and money.