Need to replace my water pump

You can put in whatever works. I'm not sure why you're concerned about such a small power draw.

Mostly I'm concerned about increased pressure in the plumbing.

My drain valves already leak, and are not accessible to replace. At least the two under the bathroom sink are not.

They mostly leak when if they are stuck in between fully open and fully closed, but weep even when closed.

But I'm mostly curious why they would spec out a pump with different operating parameters from the original when it seems like there is a pump out there that matches the original specifications almost exactly.

Original pump:
2088-403-144
http://www.fourwh.com/2088-403-144.pdf
Factory Shutoff: 45 PSI
Max Flow: 2.8 GPM
Max Current: 4.6 amps

Supposed replacement:
4008-101-E65
http://www.campingworld.com/shopping/item/shurflo-revolution-water-pump/49007
Factory Shutoff: 55 PSI
Max Flow: 3.0 GPM
Max Current: 7.5 amps

Best match I found:

https://www.freshwatersystems.com/specifications/2088-554-144.pdf
Factory Shutoff: 45 PSI
Max Flow: 3.5 GPM
Max Current: 5.2 amps

Also the physical form factor of the best match I found matches the form factor of the original more closely.

There are diaphragm kits for these. Or did they drop it with the pump?

The difference in pressure is very unlikely to cause any problems. You can easily get higher pressures if you connect to city water (especially without a regulator), if you fire up the water heater from a cold start with all the taps firmly shut, or even due to the momentum of the flowing water when you turn it off quickly.

The only reason I can see the power draw being a problem is if the branch circuit is underspecified and has a 5 amp fuse. If that's the case, upgrading it is not a bad idea regardless.

I would go with the newer model myself in your situation. The shutoff pressure is apparently adjustable, by the way. Setting it to a lower pressure and perhaps installing an accumulator tank (if you don't have one) so it doesn't cycle too much would be reasonable if you wished to do that.

SoundGuy wrote:
The Shurflo Classic i.e. -144 model - has been discontinued. The Revolution is a perfect but much better performing replacement ... own one myself. :)

Same here. Our old pump was a 1990 version also. Replaced a couple of years ago with the 4008 (Revolution). Has worked very well.

The Shurflo Classic i.e. -144 model - has been discontinued. The Revolution is a perfect but much better performing replacement ... own one myself. :)

You can put in whatever works. I'm not sure why you're concerned about such a small power draw.