I'm fairly sure that the 3rd ACR during the invasion of Iraq used the original straight M1A2. It was fielded to the 4th ID as the Force XXI testbed for the new digital warfare tracking system. Also one tank battalion in 1st Cav got them so they could work on interoperability between the two III Corps maneuver divisions. Additionally, 3rd ACR as the cavalry portion of III Corps got them as well.
The straight M1A2 had a short US Army lifespan and limited to just a few tank battalions and cavalry squadrons before being replaced by the M1A2SEP and subsequent SEPv2.
All versions of the M1A2 began life as an earlier Abrams tank and are rebuilds.
I have several M1A1 and M1A2 kits, but the Rye Field Models kit builds into either early war M1A1 or M1A2. https://www.scalemates.com/kits/rye-field-model-rm-5007-m1a1-m1a2--1004296