You will need to find the right buyer. Seven years ago when I wanted to sell a GC1.5 the market was more or less zero around here and I ended up leaving it in the house when I moved out. Take an offer of $2000 immediately. Think about $1000, depending on how soon it needs to be gone. I talked to a local dealer who said it was very hard to compete when brand new slate tables sell for under $1500. (The quality of those tables was such that he would not touch them for after-sales repairs -- too many return calls.)
I also can't believe that it was $10k new. Maybe something got lost in the translation. Or Pops was treated very, very badly by the salesman.