Australian M113A1 w/T50 turret aren’t referred to or designated “AS3”. The A1s were fitted with T130, T130E1, & Diehl (now DST) 513 tracks over their lives.
The upgraded & stretched M113AS4s are fitted with T130F track that resembles the old Diehl, but has bolted on track pads. Some were trialled with Soucy composite reinforced “rubber band” track.
At one point, the planned upgrade of the A1 fleet was involved normal hulls for some variants with automotive & suspension upgrades (M113AS3 - not proceeded with) & stretched hulls for other variants (M1xxAS4).
The upgrade project (Land 106) was a bit troubled. At least three different prototype turrets were tried: I was the mech inf platoon commander for one of the earlier turrets back in 1998. These were fitted to M113A1s hulls that had been modified with M113A2 suspension (shock absorber added to the second suspension station/swing arm & idler raised by ~2”/50mm).