If you're willing to be 45 mins north then the Courtyard on Hutchinson Island has a lot of promo's going on... check out the MR page on marriott.com. It's straight shot up and down I-95 or US-1, not far at all.

Courtyard Hutchinson Island Oceanside/Jensen Beach

Ocean view rooms are as close as you can get to the ocean and it's a super quiet property.