I am trying to identify the origins of The Zucchini Song, also known as "The Pickle Song". Most famously, it was sung by Tim Curry on Saturday Night Live. The chorus is:
Oh, what a beauty, I've never seen one a big as that before
Oh, what a beauty, it must be two foot long or even more
It's such a lovely color, so big and round and fat
I've never seen a zucchini grow quite as big a that
Oh Oh, What a beauty, I've never seen one as big as that before.

I am trying to find out who wrote it originally and who owns the rights. I was informed it was an old British Pub Hall song, but can't find it. Can anyone help direct me?

Thanks in advance!