Looks like a very early Nexstar.
https://www.cloudynights.com/article...exstar-8-r1478
http://www.company7.com/celestron/products/sch14.html
The mount is likely to fail at some point due to its age (and you say the hand controller doesn't display anything) so if I was buying I'd base my offer on the value of the OTA only, or maybe with a token $100 extra for the mount. See attached screenshot from Ed Ting's site.
And since the OTA doesn't have a standard Vixen rail, you'd need to replace it (assuming the OTA has holes for the normal rail).