Broken teeth, well ridden with little or no PM and looking pretty crusty at this point. Most of the wear on a sprocket is actually on the underside, but from what I'm seeing I don't believe it is worth servicing at this point.

I have a spare 13-26 Shimano of the same vintage. Let me know if this is of interest to you and we can work out a reasonable price. I'm also about to clean and service a modern Mega Range Shimano 6 speed. It's all chrome so it doesn't have the final black sprocket like most do. However, you have to like 13-24 five speed with the added bonus of the 34T bailout.