I use automotive acrylics mixed at a professional paint store. For Black you will need to match the finish rather than the color. If it is a semi gloss, then buy semi gloss. Flat Black - buy a flat black. The amount of paint should be no more than a 500ml for the inside of the cabinet. You are mixing 40 paint and 60 thinners, so that's a litre just for the inside of the head and body = plenty.
For the cabinet, I use a litre of primer/filler per cabinet. Around a 1.5 litre base color. If you are having the exact color matched, it works out better to buy more paint.
