Have a look on pinterest, where people have redone faucets and shower surrounds. Usually from brass to dark. They use a sanding, primer and good automotive spray paint method.
Everything will scratch eventually, but it sounded pretty solid. Just make sure you don't wear lots of rings when handling the tap. If painting won't work for some reason, you might think about re -plating your unit another metal. Usually about $50, at least where we live...
Hope that helps, best of luck!

Unless the faucet is powder coated prior to assembly, I doubt you will find a coating operation willing to disassemble and reassemble all the parts and guarantee no leaks, etc. It would certainly negate the mfr's warranty. I had a chrome faucet plated and afterwards it took two attempts to assemble it plus purchase replacement parts to get it to work properly plus multiple plumber visits. The client made the decision to go ahead with the process knowing the downside. It was the perfect shape and size for her very expensive solid bronze vessel which was a work of free-form art. There are many black faucets on the market now. I strongly suggest you look into purchasing one rather than going the powder-coating route with your existing faucet.

Good advice from all above.

Failing that and if you want to be sure, IKEA are trying to ramp up their kitchen department (so now is a time when they are producing better quality stuff to try to win people over!) - why not just replace your tap with this one. They offer limited warranty for 10 years. Could save a lot of hassle if you really want it.

Thanks for all the advice. I live in New Zealand so we don't have ikea. But love that black tap.

You can probably order this online and have it sent to you from Australia - but first check Oz and NZ fittings are the same - all the best

Because the manufacturers these days want you to repurchase they use bottom of the line powder coating which is on your black taps. doesnt matter how good the construction is underneath the black coating it will rust within 3 - 12 months. the black they use is a industrial black which holds moisture (yes it is the same family of blacks on your bullbars that are on the front of your 4wd) this is designed to look good in the showroom but break down over months. Custom powder coating when done properly and with the highest materials on the market which not many use is the best cosmetic coating in the world in my opinion. it will outlast all anodizing and chrome but not raw materials like gold, silver etc etc. regards Bling Custom Coatings and soon to be Bling Home Decor.