If you search eBay there are a ton of cases for around $20. However, when I pick mine 12.2 up on Sunday I will be getting the Zagg Cover-fit bluetooth keyboard case. (link
) I've had the original tab since day 1, almost 3 years ago, and I've been using the Logitec bluetooth case that is very similar to the Zagg case in the link. I literally have about 7 cases for my original tab at home that I've collected over the years but have only used the keyboard/case exclusively since I got it.
The Zagg is $100, which is what the Logitech cost at launch (I got it later on clearance for $15), but it's worth every penny.