from what i've been able to tell stock chains are usually size "415" or "415hd" (both 3/16" between plates) and there are no annodized or colored ones that i've been able to find. the best i've found is the kind pirate cycles sells.
but! depending on your sprockets you could potentially run "410" (hd/z/etc) chain (like BMX bikes) and there are LOTS of color options for bmx/410 chains. the bad part is they have a smaller width (1/8" between plates) leading to easier derailing and snapping often. so you've got to make sure you're engine to sprocket alignment is dead on.
i JUST decided to go with #41 chain which is the widest/strongest (1/4" between plates) of the size that fit bike sprockets, and i found some nickel plated for cheap on ebay.
the thing to consider with all of these also, is chain clearance with your tires. i'm only now able to run #41 chain by downgrading to 2" wide tires. where as with 2.25" wide tires i could juuuust fit 415 chain.
