This site shows a variety of replacement cantilever/stylus assemblies. They all appear to use a hollow tube which would snug onto the "stub" (what is the term for this?) of the old cantilever. It seems to me that there is little need for a splint:
https://orbray.com/en/product/jewel/product/cantilever.html
Was the "splint" technique-- using cactus needle(?) from a thread on the Lenco forum? I know you mentioned brass as a splint....