Really? Only $1,500 tops for a 50 year old WMP Ludwig set with original everything, plus new replacement heads? Seems low. Glad I don't plan to sell anytime soon.https://www.flickr.com/photos/30559980@N07/albums/72157629432619022
Your kit, which I saw in your link, is probably worth $2000 to $2500 I would guess. Its in terrific condition. Most sets after 50 years don't look nearly that good. My son just got a 1962/63 pre serial set of super classics 13/16/22 in WMP from Steve Maxwell for $1400 with original everything in much better shape the the OP's pictures and with no extra drilled holes, no damage to the wrap or shells except for a slight bit of damage to the inlay on one hoop, very little rust and pitting on the chrome and a much less yellowed wrap. I think that anything over $800 to $900 for the set the OP is looking at, in that condition, would be too high, and even at that price, I might hesitate because of the condition. I'm not interested in fixer upper projects, I'm interested in playing.