I originally thought it was buy one get one at gohastings but it is B2G1 for used. You can get sabotuer for 15.11 used. If there is another game you are wanting you should be able to find a decent deal.
If you don't want used, I'm pretty sure the MSRP is 20 bucks now.
Only thing I could think of would be the now expired $15 off $20 coupon codes for the EA Store. Look around on CAG, as I think a few people might have been hoarding these since the glitch last week.
If you buy it off of gamestops website used you cant get 2 copies for 35.98. Add the 16% coupon code (CAG16) and that takes off $5.16 If you have an edge card take off another $3.60..overall you could end up getting 2 copies for 27.20. The bad news there out of stock for the 360.