[Laser] Trihedral prism source?

[Bob Heath]

Don't forget you can make a pretty efficient reflector from simple parts.

Almost any magnifier lens placed close to it's focal distance from a 
small piece of 3M
reflective tape (perhaps from an old pair of running shoes, or safety 
jacket), a small piece
of bright anodised aluminium,  or even a piece of white paper, will 
perform well.  You don't
have to be exactly at the focal point - depending on the structure of 
the surface of the
material, out-of-focus will be better.

Larger lenses are also better, as are brighter surfaces (though not 
mirrors or shiny ones).
Of course, corner cube type reflectors have other properties which you 
may need for your
trials - they rotate polarization, for example.

73, Bob,
G3UJV