What's a fair price for a Heathkit GC-1000 Most Accurate...?

[badams]

Heathkit GC-1000 Most Accurate Clock:

This unit was assembled in 1984. It has no cosmetic blemishes, still syncs up with WWV and has the RS-232 serial add-on that also still works just fine.
It is clean inside and comes with both the assembly manual and the technical manual for alignments, etc.

This link on eBay claims around $300.00.

http://www.pestingers.net/GC1000.htm

Thanks for the estimate!