As others have pointed out, you can get any top you want for the Wrangers or CJs, as long as you keep to the same body series.
Hard tops are available from a number of sources, but they do cost a decent chunk of change. They are also a lot harder to remove, when you want to enjoy the nice weather outside.
I can vouch for Quadratec, I've bought a fair bit of stuff from them. Granted a lot of it was when it was a local drive, and I would pick it up from their facility.
If you're going to purchase things from JC Whitney, I would just make sure that you're buying the same name brand you would be getting from another company. A few years back, I saw a negative review on some body parts purchased from them, that were apparently from another supplier than what was carried by other companies.