No the pc version is up on amazon as well. It's a two gun kit for $129. I'm not sure if there is a single person kit or not, but honestly the base unit is $99 anyway so it'd be silly not to fork over another 30 to make it two player.
This one has actual completed product shots and pre-orders on amazon via a well established hardware company so atm at least it's closer to production than the sinden guns. I want to see them both come out so people have options, but dems the facts.
The software example I found really works with any webcam, but the high frame rate of the ps eye is something unusual on a low end, low resolution camera and processing a smaller image obviously takes less time, so I figured that'd be the place to start. I think 640x480 should be enough, but like I mentioned in other threads, I'm not 100% certain it's enough in oddball mounting situations where the view wouldn't be straight on.