You can use iron on veneer. Make sure your veneer is the same wood as the piece to be patched if not it will stick out like a sore thumb. The trick is to cut the patch the same size as the area to be pastched. Don't buy veneer by color by it by the species of wood. If the cabinet is oak buy oak veneer if it is walnut get walnut veneer. You may have to use a stain to get a perfect match because the old wood is aged and finish as aged and will be darker than the new. LeeValley cat. is a good source for veneer(leevalley.com). I have used them for years.
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