Hello Sofia,
GOod question – you would need to ask Labmaker. They would have a stock of those blue PCBs that they may be able to sell you one in isolation (i.e. without the computer).
This being said, if you already have one (and a not-working beaglebone) you CAN take it off and connect to the new beaglebone. It is a bit stuff, likely you need to use a flat head screwdriver to slowly prise apart the black headers, and do so iteratively moving around the device so you don’t bend the pins too bad
.
