I played with using Nano's as the receiver intending to hook it up to the RPi serial. But, for some reason the radio traffic on my Nano's was garbage. I tried Pro Mini's next and while they would connect to the RPi great, they were 3v3 devices and I couldn't find 433MHz radios that would work with them. I even tried shifting the logic level with different methods (resistors, IC, diode) but they all failed. I eventually gave up and am just using an Uno I had sitting around with an Ethernet shield that I had. It's working great but will require a second box rather than being connected right to the RPi.
You are looking at the MySensors stuff which uses 2.4GHz, but the concept is the same.