I don't have the box any more so I don't know exactly what its is called. The side of the engine says "Mickey & Friends" and it says 1974 Tomy on the bottom. For what I know the train came in a big set originally which had a one of a kind Mickey Station and was made available later (I think) as a normal three unit like the one I have in the picture. It also came with four Disney characters, Mickey & Minnie Mouse and Donald & Daisy Duck, which are harder to find because they are small and quite likely lost.
https://www.youtube.com/watch?v=bqN_1cd6SoU
https://www.youtube.com/watch?v=bqN_1cd6SoU