Good Point. I just sent honlite a message and see what they have to say.I would recommend sending honlite a message and ask about your specific model required. If they bare the name on the pump, they will have a replacement. Seeing as Neptune clearly didn't design the pump, I would bet money that they cannot keep the manufacturer from selling replacements directly to customers. I would have said honlite might not sell individual units, and require a minimum order quantity, but that clearly isn't so, because they have an entire aliexpress store selling individual units lol.
To be honest I probably wouldn't bother trying to find a replacement motor, as the seller seems to allude that it is custom made or modified for the task of peristalsis. I would try to find the whole unit. It may end up costing you just as much as sending it in for service, but if you document your work, others can save a lot.
A slight bit of sacrifice on your part can save the community as a whole a ****ton of money. If you have this issue, 100 other people will also have this issue. If all 100 of those people went out and bought new DOS pump for $300 then the community as a whole just lost $30,000 to Neptune. When they could have just spent ~100 per person. ($10,000) Just making this thread and drawing attention to the issue of motor failure is awesome work @2mk in doing this you probably gave a lot back to the community already.