for rust removal try rust removal gel.
it works great for light-medium buildup and it won't wear out the existing chrome.
you can get it at any hardware or auto parts shop.

for heavier buildup, try electrolysis.
it's a simple process and will completely remove the rust from any metal object.
you may have to rechrome if you use electrolysis, as it wil affect the existing chrome finish.
all you need is water, houshold washing soda, and a power supply that can put out 2amps of continuous charge, like a automotive battery charger. you can find complete instructions online.

for rechroming, try this
http://www.caswellplating.com/kits/plugnplate.htm
it's fairly cheap and works great.