Here's an article about the Kakeibo - https://tamagotchi.wikia.com/wiki/Chou_Yakikuri!_Tamagotchi_Kakeibo
And here's an article about the Dekas. Go to the 'home deka Tamagotchi releases' section. - https://tamagotchi.wikia.com/wiki/Deka_Tamagotchi
Looks really cool =D I have a large sticker on my laptop of Mametchi, Memetchi, and Kuchipatchi.
The only problem with that sticker design you shared is Version 3 isn't supposed to have a keychain right at the top/middle.
English angels go for more than the Japanese ones.
Ones that are new in box are indeed rare and often go for about 50 pounds.
But used ones without packaging are around 20 pounds.
I have one that looks similar, except it has words at the top and the packaging looked different. Here's a topic I made about it - https://www.tamatalk.com/IB/topic/192185-has-anyone-had-this-vpet-coding-before/
I've seen them before; they are rare and only released in certain countries, I think.
Anyway I rearranged my Tamagotchi shelves; there are still several Tamagotchis and merchandise not in the photo though.