[Big Dawg]

You used to be able to buy the Kalt brand from B&H photo and it would allow focus to infinity. They work great and I have 6 now attached to different lens. The Kalt Brand is now a discontinued Item there but the General brand one is an exact copy.
Go here for a look....
General Brand | Pentax-K Body to Universal Lens Adapter | B&H
Dawg