Sigma 18-50 EX DC MACRO + Pentax DA 50-200 is a good starter kit imho. But to be honest, if your new to it, get the 18-55 + 50-200 kit. It should be cheap. Shoot for a few months and you will see what you miss. None of them are bad lenses, no matter what people tell you. The 50-200 is insanely good per $.
Buying expensive lenses before you know what you shoot and how to use the camera is a mistake. I did that, I spent alot on the Sigma 18-50 (well not alot, but half the house price) because people kept telling me kit lenses suck.
Now, I never use my Sigma, not because its a bad lens, but I rarely have any use for 18-50. Had I stuck to the kit lens from start, id known that and saved a bundle for lenses I would use.
EDIT: Reread your post. Get the sigma instead of the kit and the 50-200
EDIT2: And when your done evaluating your shots, get the Super takumar 150mm and the Super takumar 200mm and never look back