They were factory fitted to all HD / 130s before the Wolf wheel came out which replaced it. My old 110 V8 HD Hicap had them, I replaced them with wolfs and stuck them on an old series 2a.
Vass used to sell them off at £20 a rim or £40 with the old 12ply 7,50 Michelin road tyre, these were all off snatches which had been re-equipped for Iraq. Those old 12 ply Michelin’s were a nightmare to remove, sidewalls were about an inch thick, my tyre machine wouldn’t touch them, it would just jam up so I had to bar them off manually.