This style of lathe was sold under many different names, so asking Jet for parts may not yield much. The nice thing about machine tools is once you learn how to use them you’ll also have the means to fix them when needed. None of the lathes I’ve owned had any factory support, and several were used to make the parts needed to fix themselves.
If you’re running a business and need to have a tool that runs 40+ hours a week to meet production then buy something new with good support. If you’re a hobbyist or small business owner, and are willing to tinker this Jet will likely serve you well for many years.
There’s way more support on this forum then you’ll get from most manufacturers anyway so there’s that. Older Taiwanese built machines are usually built pretty well, I have several. Ask the seller to send you a video of it running if you’re worried about wasting the drive but it looks clean and well cared for in the picture you posted.
John