Nope, no pre-ban yugo's. All of them were built before the ban, but none were imported (that I know of) till after the ban, and in this case, importation date is what counts.
Any idea when yours was built compared to his? Could just be a sligh change in the manufacturing from one run to another. Do either of them have night sights? If so, is one painted on instead of being the little tubes of radioactive stuff (had a brain fart- forgot the name). The ones with tubes are newest (mine is like this, was built in 1989), the paint is next oldest, then the one's without night sights. There was a sight that had gathered info and figured out manufacturing dates based on the first letter in the serial number of the Yugo's, but I can't seem to find it right now.
Basically, the pinned screw is nothing to worry about though.