Chris.
A tapered pin can be made by cutting a tapered groove into a block. If you do not have a milling machine to put the tapered groove into the block, you may be able to rig someting up with a Dremel tool or set a cutter into the headstock of your lathe and run the block across the cutter at a small angle while fixed in the cross slide. When the groove is cut the wire (brass rod) can be laid in the groove and filed to the taper angle you cut into the block.
david