as long as the paints are the same brand you shouldnt have any problems. But just to make sure id check with the rep from whoever your buying the paint from. What are you gonna be using a single stage with a flattening agent?
you can actually take that paint to finishmaster or any paint store and they can tint it close to any color.....we took a fender off my buddys red s10 and they matched it pretty close for being a flat color.