I am the second owner of this glidecam. I bought it last year off of Stephan Chaikovsky, who used to be on here a lot, but I don't see him as much now. When he had it, he did some minor modifications to the mounting plate and weight slides at the bottom (pictured). The modifications are so minor that they are negligible and basically invisible, the glidecam works completely normally. I undid these modifications that he made by reinstalling all of the factory screws, but there are still cosmetic marks where he changed it.
I purchased this a year ago for just under 300 dollars, and its value has not depreciated whatsoever, it flies equally as well as it did when I bought it, so I'm pricing this at:
255 + shipping
Here are the images (Manfrotto 577 mounting plate NOT included, I didn't want to take it off in case I need to use it before I sell it.)
Bottom Plate Modification - Zoom in next to the screws and you will see how the previous owner drilled in the slide to widen it to fit his own screws. The factory screws fit fine over this modification, it causes no issues.
Mount Plate Modification - Look at the drill hole on the right side of the picture, this was added by the previous owner to hold his quick release onto the mounting plate as tight as possible. I removed the screw, but the hole remains. Does not affect performance.
Extras - I'll throw in all of the extra screws, nuts, and bolts, as well as a quick release plate. This is the QR plate that the previous owner used, so if you want to use it, you can use the drill hole in the mount plate to secure it tightly.
Shoot me a PM if you're interested.