The supply of XM193 online is the best it's been since late 2004. but prices are up ~15%.
Ammoman - $229.00 delivered - a few hundred thousand rounds, at last count
Northwest Loading Supply - $233.65 delivered - unknown inventory
Outdoor Marksman - $220.19 delivered - 57,000 rounds
Both Northwest Loading and Outdoor Marksman are located in the NW USA, so shipping charges will vary widely depending on your location.
And if you're willing to sort through loose ammo to save some money, you can also pick up the XM193
PD from Ammoman - $199/1000 delivered, Outdoor Marksman - $177.95/1000 NET, and Sportsman's Guide - ~$177/1000 delivered (with coupon) - $53.00 cheaper/1000 than the XM193!
Prices and availability, updated daily, tacked at the Ammunition Forum - the
Ammo Price List.