If you really hit a roadblock, I recently designed and 3d printed these for a project I'm doing. I plan on airbrushing them with Molotow when the humidity lets up here. I tried Testor's aluminum Metallizer but apparently it won't stick to the 3d resin, and it looks like BLAH_BLAH_BLAH_BLAH when painted over primer.
These are 5-lug, but are easily converted to any bolt pattern. I had to play around with diameter and backspacing a bit too to get them right.
It might not be as cheap or easy as finding them from a kit, but it's an option.
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Probably not as easy or cheap as finding some from a kit, but it's an option if you need them.