68 B-body ac heater core

Looking for some advice on where I should buy a heater core for my 68 Coronet with air conditioning. Mine tested okay but don't want a future leak, and while it's all apart now's the time to do it. Some of the re-manufactured heater cores look better than others, any brands better than others?

Thanks, Mike.

Call Glen Ray radiators, they might be able to recore it. They do great work and with using an original you know that it will fit.