I used to work in industrial PM and vibration analysis, and later worked with chemical metering and feed systems and we used all sorts of pumps. everything form very small flow rate positive diplacement pumps like our RV water pumps and even smaller, to much larger centrifugal pumps
Vibration isolating mounts can help for sure
I don't believe that anything will actually silence something like this though, but you could probably get close with some crazy over the top isolation box that completely surrounds and insulates the pump and isolates it form the structure.......
Putting it under a bed is just stupid.
I'm lucky that mine is under the kitchen cabinets, but no matter.... I can still hear it.... and my hearing is bad!
A properly sized pulsation dampener is likely the best first step though, and one I will eventually try. I haven't installed one, nor have I reserached the sizingh of them, but my intuition tells me that the little ones they sell for RVs are not big enough.
Shurflo Accumulator Tank - Shurflo 182-200 - Fresh Water Pumps - Camping World
FYI, the ones we used to use were like this
Pulsation Dampeners and Surge Suppressors - BLACOH Fluid Control
Anyway, I plan to instal a pulsation dampener some day
and if my pump was under the bed like yours, i would consider a bedside switch to turn the pump off.