color switch from full black iPhone to "white AND black" iPhone

so i wanted to do some color changes in my iPhone and it includes the charging dock and headphone connector... as you may know the inside of both depending on the color it shows inside the dock connector or headphone jack..... this is a cool feature for me but there is an O ring outside these connectors that can be taken off also.... what i wanted to know is if anyone knew where i can buy these small O rings or if there is any at all in the market... Thank you