My Triton and Ariel both have rope/wire halyards, the triton is a wire>rope splice, but the ariel has a small double link between them with a thimbled eye splice in both wire and rope. Link is a single peice, but has a double link chain look to it, made of bronze, and is a lightning bolt like Z shape in profile. I'll try to remeber to get a pic while the mast is down.
Haven't sailed her yet, but finaly got the mast moved around and had a chance to inspect it, PO claims everything is original, (spent MANY years in dry storage) so it may be an off-the-shelf item somewhere. was raining heavily so I didn't play with it to see why the Z shape was required or even if it was, from a quick look it may just be to keep the wire off the mast.
When I got my triton, I looked into replacing the halyard with stayset or some such, but the required changes were more than I wanted to mess with, so I just had the splice done.
Making the conversion, means that future changes can me done with greater ease, but realy only a concern if you plan to keep the boat for the lifetime of a new halyard.