Usb bottom

Hello Guys good afternoon, so recently my father give me a old cdj 900 with the mixer 850 , but the cdj was in a terrible condition, so i talk to my friend and asked him why the usb wasn't link with my computer , and he told me that was because the usb bottom link was broken, and i want to know with this bottom is expensive to trade, because he told me that maybe this bottom can be together with a plate inside the cdj, so basically the usb bottom is missing some links and i want to know with it is expensive, thanks for the attention