What I have gathered from the bearing house we use at work is CR (Chicago rawhide) and National seal are the two main suppliers of speedi sleeve type devices. You will probably be able to find them from one of the common vendors, listed by the engine, but you can just go by the measurements and use the bearing house as well. You can just take the piece to the bearing house and they will measure it for you, if you don't have micrometers/calipers.
