I'm not sure if this is right, but I heard you obtain one by vending 10,000 items?

If not, how else do you obtain one other than buying it from someone?

yea its a prize for vending 10k items

I got one once I'd vended 10k items C: And I don't think they removed that. It just doesn't tend to show up till you get it. C:

Oh okay! Thank you and

It's also a November 2006 Donation Present Item so you could get one randomly by opening a Nov 06 DP or happen to vend one, since vending machines give out donation items.