USMC OOB 13 UNIT 281 Weapon 204 is listed with an HE of 12 and a ROF of 6. It is listed as an O/M Rocket Arty with a Unit Class of 31.
I believe the HIMARS has six tubes rather than 12 and a rate of fire of 1 would be more appropriate although it can fire all six tubes simultaneously.
This unit, as an on map unit or a unit class of 137, would enhance game play experience as firing one tube of CM or HE munitions is not as lethal as the current O/M rendering of firing 6 tubes at once, IMHO.
Sources:
http://www.army-technology.com/proje...s/himars1.html
http://www.marines.com/operating-for...ehicles/himars
http://www.lockheedmartin.com/us/products/himars.html