Argus drops the Rare/ex version of this, the Peacock Amulet. It took me 2 weeks of camping Argus (8% drop rate) to get this and 0 gil. Any dedicated FFXI player can do this. The hardest part is getting the ToD. Once you have that, just be sure to use widescan incase the LK pops since it shares the spawn window.
Ancient Torque will never replace PCC for three reasons:
1. Ancient Torque is harder to get. The drop rate in the BCNM for PCC may be 10%, but you can do it as long as you have seals. Ancient Torque drops off of Lambton Worm, so good luck with that.
2. This is level 30 vs. 74. I don't know about you, but having to wait until 74 for a good acc. piece seems rather lame!
3. PCC has ranged accuracy. Ancient Torque doesn't. For what RNG cares, Ancient Torque is useless to them.
You can get this one on BCNM40 "Under Observation" to get it. Best and easy way to kill this mobs is to have 3xBLM/WHM. Use tav tacos for the added def, blink, auqaveil, ice spikes, barfire, and a yag drink. Facing away from the mobs, use StonegaII at the samt time. After that, just spam -ga spells like thundaga, blizzaga etc. GL