My Strat is soon to get the BKP treatment. It's going HSS, with a chrome covered Holy Diver, and then 2 Irish Tours with the usual white covers being chrome plated...
It's an extra £10 to get them chromed, but if they can chrome plate singles then they may well be able to chrome plate HB bobbins - but they're plastic underneath so they can't be burnt
The best way to find out would be to PM Tim and ask him, and then report back here as chrome bobbins might look better than a chrome cover on my strat :P