Thank you for all of the comments and discussion. For the Jet 1642 1.5 HP, the going price these days seems to be between $ 1,000 and $ 1,500 depending on age, condition, and what accessories might be included.
I completely disagree with Paul that this lathe is worth $ 200. For many, many woodturners the Jet 1642 is one of the best lathes one can buy in its size class - you get quite a bit of "bang for the buck" given its specifications, design, and turning capabilities. For those that can not afford a Powermatic 3520 or larger lathes, this is one of the most popular 'go-to' lathes. Although I now own and use a Robust American Beauty as my main lathe, I also still own a Jet 1642 lathe (2 HP) that I have formerly used as my main lathe since July 2003 (I paid $1,200 for it then). Throughout the past 10+ years, I have not had a single problem with it, and I do not intend to sell this lathe. It is still fully functional, great for turning longer spindles than the standard American Beauty can handle, and I have many accessories for it that make it a complete "second" lathe system for teaching, for turning 2 different projects at the same time, and it also can be quickly set up for the Jamieson hollowing system. It really wouldn't make any sense to sell it!
We are going to purchase Karl's lathe for $1,000 - his wife wants our chapter to own it (probably along with other related turning items that we also will acquire) and in some way Karl will be with us at our chapter meetings even though he has passed.
Thanks for all of the comments and suggestions!
Rob