I bought mine off Ali-express, cheaper than ebay at the time. Some now come with a hose between the compressor and airbrush which could be handy for getting in tight places, I suppose, but it's getting away from the portability aspect a bit. There's a huge number of generic airbrushes available now, and pretty cheap, ranging from external mix (I have a Paasche, very handy and as you say easy to clean) to double-action with bottom suction feed, side feed, top gravity feed and a pistol grip type with a largish paint bottle on top, and all pretty cheap. I've ended up with all of these and I've got no complaints with the quality of them. One thing I did was to polish the needles, it might not be necessary for spraying leather but I did it anyway.
One of my grand-daughters is very artistic and creative and one day when I mentioned airbrushes her eyes lit up so I've "lent" her one of my compressors and a top-feed airbrush, she was very excited about trying something new. Knowing my wife I suspect "donate" is a better term.