I would like a square host myself. I was thinking about making a square battery tube with a module on each end for hand grasp that you could sight down your arm, the beams would pretty much appear to come together at infinity.
I've tried to make parallel beams using M140 diodes and quickly found from diode to diode they do not center, either due to the diodes themselves being slightly off from one to the other, or the way they are pressed into the holder/heatsink being slightly off. Close in you can't see they are pointed slightly different, but far away, they are all over the place, some close, others not at all close. From this I learned I must have a method of X-Y alignment for each and every diode (when there are more than two).