8mm F3.8 Fish eye C mount Wide Angle Fisheye Lens Focal length Fish eye Lens Suit For C P/Q for Pentax Q/Q10/Q7/Q S1 Camera|8mm f3.8 fish-eye|8mm f3.8c mount - AliExpress
Samyang 8mm F/3.5 Fisheye CS Lens for Pentax K mount SLR DSLR Camera K – Roxsen.com
0.45x 52mm Super Fisheye Wide Angle Fixed Focus Lens For Canon Nikon Pentax Sony camera|Camera Lens| - AliExpress
Amazon.com : Rokinon HD HD8M-P 8mm f/3.5 HD Fisheye Lens with Removable Hood for Pentax : Camera Lenses : Electronics