The gaming remote that came with the Roku 3 is no longer available (other than secondhand), but it will work with any of the current Roku remotes with the exception of the one that's specifically for Roku TVs. It will also work with many universal remotes that support Roku devices. If you desire the the "point anywhere" feature of the gaming remote, you'll need a voice remote (that has to be paired with the Roku 3).
One note: given the age of the Roku 3, I'm not sure it makes financial sense to invest too much in a remote. Any of the current devices will be faster than the Roku 3 and most come with a voice remote.
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