Water pump not pumping water

[ShrimpBurrito]

The TM gods are working against us. Pulled out of a site with hookups, where it had dropped into the 20s two nights in a row. I did empty the water heater and the 2 drains under the shower.

Then pulled into a site in the boonies with no hookups, and quickly discovered the water pump was kapootz. Flip the switch, the pump motor runs (although much quieter than usual), but no water comes out.

This is what I've done to troubleshoot:

1) pull off the output tube and try to pump; nothing happened, but water did drain out of the tube, seemingly indicating that the tube was not clogged. We operated fine on hookups.

2) pull off the inlet tube, and blew air into it and sucked water out with my mouth. Thus, that tube was not clogged, either.

3) reconnected pump and tried running it again again after we moved a few hundred miles to a new spot. Essentially, the "if I ignore it and shake it up a bit, it will fix itself" method. No luck.

So perhaps the pump is just dead, so I pulled it out and took it apart, but I can't see anything wrong with it. I'm not a pump tech, but the motor runs fine, no visibly torn seals, floating debris, etc.

I've looked a bit online, and have read many folks say these things just never die. So before I go out and buy a new pump, does anyone have any suggestions, either on what may be wrong or what new pump to get?

Thanks,
Dave