I did it as an antique gunsmith/ restorer/ appraiser for 30 years. do it now for fun and games.the trick here is to mix the epoxy, long set time stuff, with powdered color, dark, to make it match the fix. no glue line. then mix paint color with ture oil, (a new bottle always, and pad it until it matches. works every time. the walnut wood must match grain for grain too. and the inside must be aged too, so the repair/restoration is totally invisible inside and out.
Ken