Small cabin cruisers and RVs used to be fitted with a small hand pump. Perhaps they are still available. I'm quite sure you could use a longer pickup hose, as a few others have already mentioned in this web site. For what it's worth, the instructions that came with my Magister Stella indicated that i could drop such a hose into a jug of water placed below the counter. I have not had a look at the vibe pump in the Magister, but the one time I did open it up to see how it was built everything looked rather generic. I suspect the vibe pump is the same one seen in many other espresso machines.
I've recently installed a custom espresso bar in our house, which includes a spigot from our RO filter, which we use for espresso. I've been toying with the idea of getting a flexible hose, which I could push over the spigot, then just turn on the tap until the reservoir is filled.