P.s..... I reckon jsr or wyz will have a crack at making one lol.
First, I do enjoy refill my 0.5L paintball tank with my hill mk3 just as exercise
Second, while I was in China I ordered a scuba compressor that´s used to refill diving bottles, refills a 10L bottle to 200 bar in 20 min no need to connect to another shop compressor and only cost 400 euro. Sadly it weights 39kg, I´m still working on the shipping process