First of all, I blame myself for not researching this receiver more. I bought another receiver a while back and it "just worked" with my WMC remotes, so I expected Flirc would, too. I didn't realize that it merely mapped IR signals to keystrokes.
I have a WMC remote that, I think, came with one of my Hauppauge tuners. (It's been years.) The keys are the same as the Rosewill RHRC-11002, but its shape is more like the Adesso ARC-100 remote (but it's black).
Keys
http://amazon.com/gp/product/B005ZAK50K
Shape
http://www.amazon.com/Adesso-Media-Center-remote-control/dp/B000XVNJRM