The PCB is probably manufacturer specific and unavailable, but looks okay in the picture (?) so if the port itself is undamaged you can reuse it, or buy a new port, and solder it back on.
I mean I am taking your question to mean, where to buy the entire populated I/O board. If you just need to know where to buy a USB port to solder on, it could depend on where you're located. In the US the first place I'd look is Digikey because they offer cheap USPS shipping for small items under a few ounces.