Bob Miller, ND has offered leader 6th 3 or 4 times at public auction, former owner of this bull as well. Bob to my knowledge has a pretty deep library of old stuff and is old enough to remember many of the 70's bulls. You'll have to call him.
Larry Kohlsteadt, MO has a list of older bulls - I thought tiny tim was on this list ( last april visit). He had a fairly large inventory of a varitey of old bulls. Brian - his son is listed in many short sale catalogs.
Warren and Roger Lakamp had a pretty interesting list of bulls- Central, IL . Not sure how many they paper but they are a member of asa, so the phone number is listed. Roger worked at TPS- both he and his father, Warren are interesting to talk cattle.
I would also considered Koulee Ranch, Washington. Mr McLean has a great memory.
The year we purchased alot of Kinnaber Leader 9th - "tiny tim" was on the list as well. I got the feeling "tiny" was not the case with this bull. Gene McDonald of course is another great source. Call Cagwins for his number
good luck