Another possible solution (albeit still requiring the IR emmitters) is to use a routable IR distribution block such as a Xantech RT8. This allows you to send an IR command to choose which of the 8 addressable outputs you want to send commands to and then all subsequent commands go to that output (you can also have all on or all off if you wish).
If you already have IR remotes, this *might* be a less expensive solution than having to replace your IR remotes with RF-capable ones. However, the RT8 is somewhat pricey (and you need the Xantech RC68+ remote if you need to learn the commands into your existing remotes). If that's a path you want to go, check out eBay for RT8s... the RC68s come up from time to time too and you'll pay a LOT less than retail for used units. I have both units myself, but haven't had a use for them just yet (I thought I needed them, but in the end my setup didn't require them) so if you're interested in going that route, I may be willing to part with them.