paolo, do you have pics of your wheels, and the overspray. i'm not clear on which parts of the wheels needed refurbishing (cos i'm a little surprised that parts on-view had corroded).
you may be able to work on them yourself. without seeing the wheels, i'd have in mind to use some wet&dry sandpaper, say 800 grade, to take off the surface rust/corrosion, and the overspray or the entire layer of spray paint. finish with 1500 grade. if you haven't cut right through the original paint, then you can simply respray them with suitable clearcoat. once dried/cured, follow with some wheel sealant (ie: like wax, for wheels).
if they need a respray, you may wish to do that yourself too.
it's not a difficult process, but time consuming. you need to 'prep' the wheels properly by thoroughly cleaning them (of brake dust and grime), then sanding, then masking, then spraying.
when going 'aftermarket', the biggest issue is finding wheels that have enough spoke clearance (behind the spokes) for the Brembo calipers. unless you wish to use spacers, the choice of wheels that fit is probably quite limited.