Best Buy: HD Da 15mm f/4 Ed Al Limited Wide-Angle Lens for PENTAX K-Mount Cameras Black 21470
Amazon.com : HD PENTAX-DA☆11-18mmF2.8ED DC AW Ultra-wide-angle zoom lens 17-27.5mm (Equivalent to 35mm format) All Weather resistant Extra-sharp High-contrast images Free of flare and ghost images Smooth, quiet AF : Electronics
77MM HD ULTRA WIDE ANGLE MACRO LENS FOR Pentax HD-DA 16-50mm f/2.8ED PLM AW Lens | eBay
Amazon.com : HD PENTAX-D FA 24-70mmF2.8ED SDM WR High-performance standard zoom lens 24mm ultra-wide angle Weather-resistant construction Exceptional imaging power ED Glass Aspherical lens Latest lens coating : Electronics
The best lenses for Pentax K-3: Recommended wide angle, telephoto and standard lenses - DXOMARK
Pentax DA 40mm f/2.8 Ultra Compact Lens for Pentax DSLR Cameras
Amazon.com : HD PENTAX-DA☆11-18mmF2.8ED DC AW Ultra-wide-angle zoom lens 17-27.5mm (Equivalent to 35mm format) All Weather resistant Extra-sharp High-contrast images Free of flare and ghost images Smooth, quiet AF : Electronics