For 100 to 300 pounders, its worth the risk. The machine is old, cast iron and built like a battlewagon. Dealing with spares is like anything in the old world. Keep doubleboosts number handy if your in england. The motor appears to be direct drive to the chisel. So it could be a replacement motor now and or you can use a replacement motor in the future.
The state of modern woodworking is dismal. The new tools are overpriced and underbuilt. Pure frustration for the queens quid! I wont do it. Stick with the old names. wadkin, robinson, sedgwick, etc. Learn how to restore what you need. You will save money in the long run and you will be happier with your work.
The problem with modern hollow chisel mortisers is that the body will flex under load. So your mortise looks a bit like the rats have been eating in there. Oldies like wadkin or robinson behave totally different. My machine is a 1940 world ward two wysong miles 284 and an oliver 92 from the 1940s. These old girls will keep on running for ever. Bearings are a no brainer and are standard.