On Roku TV's Roku only supplies the UI, you have to go to tv manufacturer for oem remotes. I would go to eBay, there are thousands of Roku tv IR remotes. Look for your brand, if the Roku remote has a crescent moon key for sleep timer it's an IR remote.
Edmund
Roku Community Streaming Expert
Help others find this answer and click "Accept as Solution."
If you appreciate my answer, maybe give me a Kudo.
I am not a Roku employee.