In regards to the K-30 lacking both a stereo mic or external mic port, I'm not sure it's as much an issue now as I used to think it was. After trying a Røde video mic on my D7000, apart from reducing AF motor noise it leaves wanting just as much as the inbuilt mic anyway for anything reasonably distant from the camera, and hence also the mic. Alternatively there's a shotgun mic, which is not as distance-limited but still not perfect. Or a wireless 'lavalier' lapel-mic type of setup with a transmitter and then the reciever plugged into the camera. A boom mic on a long armature is getting into pro-territory by needing a separate operator or special setup etc. All connected to, mounted on or plugged into the camera.
Then there's the separate recorder - which doesn't need any mic port at all, and mediocre internal audio recorded by the camera is just to help sync the proper audio taken with the recorder, so neither of those things matter any more. There are a couple of models on the market and I just got myself this particular one - the
Zoom H2n:
For those willing/able to go the extra hassle to sync separate audio with video in an editor (click your fingers!), ideally without too much actual real hassle with something like Final Cut, this may be the best method of all anyway even if your camera does actually have an external mic port like the K-5 (you can still plug the line-out from the H2n into the camera and use it as a standard external mounted stereo mic). But it works even better using its own far more in-depth audio options than those built-in to a camera, amongst whch as you can see from the top of the unit you can flick a switch between MS-stereo or 2 channel stereo to 4 channel surround with its 5 microphones.
It effectively means you have an armless surround/stereo boom mic to get right into the action where the sound actually is while the camera stays at a distance - so you can just set it down in the middle of a table to record everyone around it equally well while the camera is off to the side filming, or mount it on a tripod in the middle of a group (a band or family etc) while walking around with the camera. Or put it in your pocket (or clip onto your belt with the accessory pouch) and plug a hands-free lapel-mic into the line-in port instead of using a wireless lavalier transmitter to the camera.
After trying the other option of an external mic mounted on the camera which actually makes the camera more awkward and intimidating anyway, I've decided this separate audio recorder is the better option for myself so a camera having mono-only audio or lacking an external mic port is no longer an issue or negative for me. Especially now as an added bonus it's 'backwards-compatible' so it will now also give video from my mono-only GXR a whole new lease of life!