Get yourself down to an industrial fasteners place, there's bound to be one near where you live, and they'll have more sizes than you can shake a stick at. If they don't stock chromed bolts they'll certainly be able to get them fairly easily. Personally, I'd use stainless, it will polish up just as well as chrome and stay like it. Having said that, I've got a scattering of silver plated and titanium on mine (proper ones aerospace ones, not the kit rubbish) - shame I don't work in the industry anymore...