What do you use to support the camera and lens? Tripod, monopod? My first suggestion is that your shutter speed is very low, a shutter speed of 1/focal length or faster is normally recommended. Seeing that you're at 300mm, 1/300s or faster would be recommended.
I'm no great wildlife photog, but when I shoot birds etc I usually go for ISO400 right from the start. I reckon on the K-x you could use ISO800 with no problems. This usually ensures you have a nice fast shutter speed, which helps with lack of sharpness due to camera shake.
If you are using a tripod, I suppose you can ignore most of this...
The overexposed snow in your photo is quite distracting unfortunately, so you would need to change the exposure in some way in any case. If you went to ISO400 that would give you about 1/300s shutter speed, and you could increase that shutter speed some more to expose for the snow, or at least stop it from blowing out
I would suggest that in widlife shots it's probably most important to expose the subject well, and it looks fine here, but you also need to try and avoid the harsh background distractions.
Have fun, it's a nice subject and I would like to see more.