Lots of hits on google for that radio, DFRobot.com seems to be a source for them.
https://www.google.com/search?hl=en&source=hp&q=apc220+radio+communication+module&gbv=2&oq=apc220+radio&gs_l=heirloom-hp.1.0.0j0i22i30l6.1076.3822.0.12293.12.10.0.2.2.0.312.1638.0j2j4j1.7.0....0...1ac.1.34.heirloom-hp..3.9.1638.WWko2bZDR20