Being the biggest-selling record ever, 4.5 million copies sold, there are tons of copies around (even for a record from 1976!) so mine only cost $1.99 ^_^ I already had a copy of the song on a compilation CD, but it's symbolically nice to own a copy of such an important record.
It's a bit like the story of the gingerbread man, it's a short children's song animation. You can watch it here
Every day the baker makes taiyaki and it gets eaten. One day, the taiyaki gets bored of this, gets into a fight with the baker and decides to escape, and it goes off and swims in the ocean. It has a nice time there, lots of fun swimming about, but eventually it gets hungry. So it looks for some food, and sees a worm hanging about in the water.... some old guy fishes him out! What a surprise! So he gets eaten.
There's a live version here too:
http://www.megavideo.com/?v=XPHOOBLL
Hooray for Masato Shimon! Isn't he great? Why is he surrounded by businessmen, clapping? Well, it seems that the reason this was such a big hit was not just because it's a great song, but everyone in Japan could relate to it as a metaphor for working life.
...isn't that somewhat depressing? I guess it depends on your interpretation.
Apparently due to contracts, Masato Shimon didn't make much money out of this at all. :( The record company made enough profit to build a new building just from this one record, though.