Amazon.com : Fotasy Adjustable T/T2 Telescope Lens to Pentax K Mount DSLR Camera Adapter Ring, Compatible with K-70 K-1 K-3 II K-S2 K-S1 K-3 K-50 K-30 K-5 IIs K-5 II K-5 K-500
2 Inch To T2 M42*0.75 Telescope Eyepiece Mount Adapter+t For Pentax K - Decorative Telescopes - AliExpress
Pentax K SLR / DSLR 2" UltraWide True-2 Prime Focus Adapter - TelescopeAdapters
Amazon.com : 2inch Telescope Camera Adapter for Pentax K SLR/DSLR - with 2” Filter Threads : Electronics
Lens Adapter Astro Edition - 48mm T-Mount Wide Field to Pentax K Cameras – Fotodiox, Inc. USA
General Brand M42/Universal Screwmount Lens to Telescope BT831
Pentax "Q" Mirrorless Prime Focus Kit (1.25") - TelescopeAdapters
Pentax K SLR / DSLR 2" UltraWide True-2 Prime Focus Adapter - TelescopeAdapters
Amazon.com : Alstar T-Ring and M42 to 1.25" Telescope Adapter (T-Mount) for 42mm Pentax-k SLR/DSLR Telescope Cameras.(for Camera K-x, K-r, K-01, K-30, K20D, K200D, K2000, K1000, K100D Super, K110D, Etc). : Electronics
T Ring For Pentax K Camera Lens + 2inch To T2 M42*0.75 Thread Telescope Mount Adapter - Black - Lens Adapter - AliExpress