I found some great laser tech videos from a company called American Photonics and while browsing the store noticed they sold combiner lens’ for reasonable prices so I upgraded my mount(and K40) with this so others could more easily upgrade their K40 too.
Previously, I’d purchased a piece of used medical equipment with a combiner lens off ebay and used that. But it’s not like anyone can go buy that same lens and mount and have a working system.
This design is cleaner and new and the lens has a supplier. It’s a less adjustment mount but OpenSCAD and Thingiverse have Customizer for you to tweek the design parameters as needed and it prints pretty quickly.