I think the better bet might be buying them through the Origin Store, both 360 and PS3 versions are $19.99 there. Granted you'll have to pay an additional $2.50 for shipping but it will still be cheaper then the 360 version on amazon and it might be a better option for the PS3 version if you can't find anything else worth buying to be eligible for the FSSS.
Also, the origin store is currently running a 20% off 2, 30% off 3 and 40% off 4 sale.