I replaced mine after the original fire. I believe the hour meter is part of the circuit and without it the circuit isn't complete. I also believe it is designed that way so the average person can't just unplug it to keep from racking up hours without being recorded. It is a way for the next buyer to know haw many hours are on the machine, so to speak.
The schematic should verify this but I don't think they give the actual specs necessary if there are any. I may be wrong and you may just be able to just jump it out with a paper clip, but I doubt it.
$70.00 isn't really that much when you consider the cost of the whole machine.
I would tend to keep it original parts, if for nothing else resale value. Nothing is worse than a cobbled up machine for resale.