I think they're VERY rare...I've only seen one on ebay like once and it was atleast 100 bucks! FOR A TAMAGOTCHI!!! I mean sure it's rare but THAT much?? The only possible way to get one is if you have loads of extra cash and go on ebay every hour to check if someone recently posted one for sale!
They seem to be really rare, and VERY expensive! Roughly the higest amount is over 200
My friend has actually got one, her mum got her one from ebay, and she actually got it really cheap! Some people don't know how rare something is when they sell it! She got her's for only 20 pounds! When i told her how rare it was, and how much it was worth, she was really amazed! Lucky her... *Goes green eyed*