Sorry to hear of your circumstances. The point about PF posts is that they only refer to the available data. Many PF replies are of the form "If you have a nuclear reactor you can . . . . ."
Wherever you want to take this spread laser beam you will need a sturdy construction . If you base the mounting system on tubes (metal or cardboard, you will probably find the result will be the most stable.
Good luck with the project which I now understand is very 'part-time'.