Pentax K10D has a Pentax KAF2 lens mount and currently there are 163 native lenses available for this mount.
The latest released lenses that are compatible with the K10D are the Pentax FA 50mm F1.4 Classic, the Pentax FA 50mm F1.4 and the Pentax 16-50mm F2.8 ED PLM AW.
K10D also has a sensor based image stabilization system which means that all of these lenses will be stabilized when used on the K10D.
Since Pentax K10D has a APS-C sensor, it has a focal length multiplier of 1.5� so you have to multiply lenses original focal length with this multiplier to find the Full Frame equivalent focal length of the lens when mounted on K10D.
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Pentax K10D Lenses with Image Stabilization
Pentax K10D Lenses with Weather Sealings