You can use them all and make them work. For the top, mouth piece, of the striker if you don't have a hen radius bone, simply take the radius of a jake or gobbler and add permanent adhesive such as JB Weld or even better Apoxie Sculpt (both two part epoxies) into the hollow of the bone about 1/2" and let it set for 24 hours. Take a 3/32" drill bit and drill out the suction hole. It is the 3/32" suction hole which is the key which is why hen radius bones work so well. You can use a Dremel tool and various abrasive attachments in combination w/ fine files such as chain saw files to thin the ulna (which you don't normally need to do except to make the bones fit and seat better) and the humerous which can be cleaned and thinned to produce a clearer more resonate sound. I prefer the external diameter of the radius from a jake or gobbler and they make a more substantial, less fragile, yelper.
Craig