However, we would like to know your opinion on what collectibles can be personalized and are there any sites or people that provide such services? (or perhaps there is one of the manufacturers of collectible items here on the forum).
Several hardware wallets are already offering co-branding solutions.
I recently did a research about that for one of our local member campaign, so I am posting more information about that here with links.
Please note that I don't support any closed source wallets, and my suggestion is to avoid doing any deals with them, plus ledger nano X is one of the worse hardware wallets with many issues with battery, and that is a big reason to avoid it
(S+ is better and cheaper).
However, I will be be neutral for co-branding and just the post links, for ledger that is:
https://www.ledger.com/co-branded-partnershipSecond option is OneKey hardware wallet from Hong Kong, they started as Trezor fork, but they are most popular hardware wallet in China, and they are open source:
https://onekey.so/co-branded-partnership/CoolWallet (they are closed source):
https://www.coolwallet.io/cobranded_card_partnership/Keystone wallet is open source and you can contact them for potential co-branding:
https://keyst.one/Satochip is also doing custom crypto cards, but someone already mentioned them above.