Noob requiring help with project

[steeldemonuk]

I know a very limited amount about electronics and therefore I apologize in advance for not knowing enough to know I shouldn't have asked something.

I am trying to make something, which in my head, should be quite straightforward. I wish to make 2 small units that can signal one another via RF. I intend the units to be around the size of a keyring reel (picture attached) they will have a button on the front which sends the signal to 'page' the other unit and you can select between a beep/vibrate/LED flash to be notified. I just need someone to advise me on how to do what I want to do, even if the information is a company I can go to to get units made. I am aware that there are things out there that do similar, but I would like to make these units my way.

Hope someone can help.

Regards and Thanks

Alex