AZConcept

Nothing simpler than making a low cost but efficent collimator:

For the PVC tube the household sewer tube can be found in any shop.
To get the required concentricity, the best is to do both at same time:

For the cross hair I printed it on a paper including the hole in the middle (concentric ellipes and cross).
Centering the laser pointer in the tube wiorks quite fine with six screws.

To fit the 32mm exterior PVC tube diameter to the 31,75mm fix it into a drill or lathe and use some abrassive paper to reduce diameter.

And that’s it.
Have a look at the beast!

The complete drawing is here Collimator_Drawing