Be a piece of cake, I suggest buff horn.
Coat the flat surface of the horn or whatever, with thin ca first, a lot of it will absorb into the small pores if it's antler. Let it dry for 10-20 minutes. Hit it with 60 or 80 grit paper. Blow the dust off it and apply thick ca glue to both surfaces and attach it on the bow tip with about 4 rubber bands wrapped as tight as you can get them. It will be fine then.