Thanks for linking those. I’d seen the snail one on a few Peaks in the 1980s when they were transferred to Tinsley, and I remember the rabbit one now. But like you I don’t think I ever saw a sheep emblem on anything.Can read about the Railfreight depot logos here.
InterCity Depots also had some badges created just before privatisation - I have a set of badges but need to take some pictures. Interestingly there were no badges for the East Coast depots though.
Few more can be found on the Hattons site. Never seen the South Wales Sheep or Tinsley Snail before!