I think the second link with the collimating lenses is more what's needed. I was just looking at another page and saw that you can also buy collimating reflectors which might be cheaper than lenses. I wonder if that's something you could 3D print and then coat with something to make it reflective. It'd probably be better to build a tool to punch them out of stainless steel sheet metal and then polish them to a mirror finish.
Found these. Main use is horticultural?