Honestly, hard top prices are very, very regional. In some parts of the country, people will literally give them away. I live in SW Missouri (15 minutes from OK, 30 from KS or AR) and here, they're like gold. A hard top (without the doors) in the condition that you describe would bring $700 minimum. I'd look around on CraigsList in your area. It won't take long to notice a trend.
“The test of the machine is the satisfaction it gives you. There isn't any other test. If the machine produces tranquility it's right. If it disturbs you it's wrong until either the machine or your mind is changed.” ― Robert M. Pirsig, Zen And The Art Of Motorcycle Maintenance: An Inquiry Into Values