Thanks hybrid & Thor, glad I asked. The $600 was a craigslist price, expecting potential buyers to bid me down from there. But the Ebay strategy sounds better, never sold there before so this is very helpful. I would just be afraid of letting the frame go for $300 since decent new frames are usually $400 & up.
Also, I've decided to rebuild the replacement frame since I don't know when I'll have the few extra $$ for the Casseroll &, frankly, I need to have both the frames for a side by side comparison. The fact that the "new-ish" frame will have, say, 500 miles on it (with no scratches,etc) shouldn't affect the $400 reserve/$250+50 starting bid, or am I off on that one?