I would hazard a guess that as 1992 was the launch date, there aren't many left that still work. Whether that makes them sought-after is something else entirely. Great little computer for running System 7 though.
Pre-G3 Powerbooks are few and far between on eBay these days. Those things used to be abundant back in 02-03 but now its getting harder to find them. I would bet you could find someone to buy it off you. As for asking price, no idea.