Unfortunately there is no technology advancement on the water pump. There is very few company that makes them (Pentair, Aquatec?). One possible thing to look for is induction motor, but that can complicate the control circuit, and make it more costly. If you care about the amperage, you will either need to settle with lower pressure, or lower flow rate. Another alternative is to mount the water tank on the top, or separate water tubs (6 in PVC on both side along the side) and let the gravity do the work of the water pump.
Besides, there is only like ~30 gal of water to pump. It won't take much energy overall before your fresh water tank is empty.
2000 Concourse dinette, on 1999 6.8L Ford E350 Triton V-10 Chassis