You will find a $1/1 Target printable coupon here that can be stacked with the $.50/1 printable manufacturer coupon here & here.
Buy 2 bags...use the $1/1 Target Chex mix 3.75 oz or larger coupon...stack with 1 of the $.50/1 manufacturer (4.5 oz) coupons above...for a total of $1.50 off of 1 bag (if you use them at Target) or $2 off of 1 bag if your local Publix store accepts Target as a competitor (Publix will double the $.50/1 coupon to $1)!
Tips: Look up front by the registers at Target. They carry the smaller bags there. I am not sure if both coupons will work on them (the bags may be too small) but it's worth looking into! You could also wait for the Chex mix to go BOGO at Publix for it to be a moneymaker there!