After months of requests, Retroid is now offering an official grip for the Retroid Pocket 5. It comes in three colors: black, purple, and transparent white. Price is $15 plus shipping.

Affiliate link: https://tinyurl.com/RP5grips
Non-affiliate: https://www.goretroid.com/collections/frontpage/products/retroid-official-grip-for-rp5

Of note, there are lots of great community 3D-printed options out there too. I have a video coming out tomorrow talking about some of them!