I'm going to sand and repaint my pepperpot wheels using rattle can paint. Any suggestions on the color code or type of paint thar would be best suited to deal with brake dust? Should i do a self-etching primer first?

 

Can't help on the colour code, but refinishing....

My tip is to sand, sand and sand again during prep.
I'd advise against cheap rattle tin paint and go for something by Wurth.

I refinished mine on my X type some years ago and initially used a cheap aerosol which was just nasty. I redid them using Wurth and the difference was like night and day.

I applied 2 coats of primer, around 3 coats of paint and approx 3 coats of lacquer for a great finish

 

As far as the color, I've read on the forums that autoglym silver wheel paint is what you want. Available on Amazon. The one review mentions the ogle/pepperpot wheels.