If the rearsets are alloy, both podwer coating and paint are only a temporary cover at best.
Best for alloy is anodising!
Many colours are available and they can be done to varying grades of hardness also.
As for bolys, just take them all down to your local bolt shop and they'lle able to supply anything and everything you want a lot cheaper than buying the bolt kits.
And if you want to really get carried away, go to a good tool place and get some stainless polish and a polishing mop, and mount the mop in a drill and you can polish the stainless up like chrome that will never tarnish or flake.
Otherwise I personally would go paint over powdercoat. Powdercoat tends to be brittle and chips a lot easier than paint.