SMC Pentax-M 100mm F4 Macro Reviews - M Prime Lenses - Pentax Lens Reviews & Lens Database
Amazon.com : HD PENTAX-D FA Macro 100mm F2.8ED AW Macro Lens, dustproof, Weather-Resistant AW (All Weather) Construction, Black (20320) : Electronics
Venus Optics' 100mm F2.8 Ultra Macro lens is now available with Pentax K mount, new stepless EF mount version also available: Digital Photography Review