What finish do you want? Not very helpful I'm afraid.
But, if you want an antique looking finish you can use--not sure if it's called something else there--gun bluing. It will in a matter of seconds when applied to steel turn it a kind of old bluish bronze looking color, depending on the type of steel.
The below shelf pin liners, shelf pin and hinge where stainless steel. The rust inside the shelf pin liners is due to not drying off the water after treatment (you rinse the treated steel after application). These were the first I tried this on.