I'd also suggest to buy a hardware wallet from either ledger or trezor.

However, buying from amazon is fine as long as you are buying it from an official reseller. You can find them on their website (at least that's the case for ledger, don't know about trezor).

Still, buying them directly from the official store is probably the best solution. However, the delivery charges might get expensive if you are not located in the area of the company (ledger is located in france, for example).
But you get the option to pay with BTC, which is a plus compared to amazon IMO.