Search a way to find a replacement for a unison research unico pre remote control

Hello !

I hope you are doing well !

I have a pre unison research unico with a lost remote control which s only for the volume

unison research sell only the infrared remote and not the rf remote

I search a way to find a remote or a way to "build" a remote.

If I find the frequencies and code of the remote I could perhaps use it on a rf remote 

all the best