Changing from par 30 to gu10 potlights?

i just moved into a house that went through some renovations so theres a few odd things about it. in the kitchen there are 3 potlights (dont ask why theres only 3, i have no clue). two of the potlights are old 4" can lights (where the bulb is recessed up inside) that use large par 30 screw-in bulbs. one of the potlights is a new style 4" flush potlight that uses gu10 bulbs. I am wondering if there is any easy way to convert the old potlight to match the new kind? I dont really want to tear out the fixture, patch the ceiling and install a new one. Does anyone know of a retrofit kit or something that would allow me to install a new trim piece and bulb housing or whatever, and leave the existing electrical box and everything? Thanks!