I use this for my firestick and projector remotes.

https://www.amazon.com/gp/product/B00LBK7OSY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Its a bit oversized but works fine. I put in a small piece of paper towel inside so I can quickly see if it leaks. I've had it for 2 years with 0 leaks. I only open them up to replace the batteries.