Unless you do it yourself I doubt you will have much luck finding someone who will do it at a price you want to pay. If you have, or know someone who has, a small metal lathe a cherry can be made without too much trouble. I have made several molds with D-style reamers and if you take your time they will cut a nice cavity. Also, keep in mind that getting the reamer is only part of the equation, you still need to figure out a way to set the mold up so that the cherry will cut the cavity evenly on both sides.