Could be.There has been a couple of late that have sold on Ebay in the high $3/4k bracket. They were very nice restos aswell with all the work done. Even a quick tidy up will cost. It's all those little parts that add up. Then you look back at what you originally outlayed and see your $3k KX has turned into a $5/6k resto. It depends on what sought of condition you want the bike in.
Paid $500 for my KX 500, yes the motor is in pieces but I will come out way ahead in the $$$ department when the resto is done. Just picked up a very nicely restored YZ400E. It's not a KX 500 but then again I only paid $3K. Runs super smooth and tight. Plan to have it at Conondale, can't wait.