Well the MILAN/Spike-ATGM that I posted on the other thread would most likely support your SRM weapon, after all they need 4 to move, and do 1.08 damage each. Up to the range of 2 or 6 hexes out.
You'd only need to use one to fire and three more to move, allowing the last three to fire / overwatch on the move when dismounted. AND you could also use that SRM variant Rock Rover to simulate this weapon on the move!
TT