Amazon with AAurora has the ExtreSpo Adjustable Weighted Vest (11-20lb) for $35 - $18 off with coupon code ZGEES7GQ (click here to activate) = $17 with free shipping on $35+ or with Prime. 20lbs to 32lbs option is $27 with the same coupon/ link. 

Amazon promo codes don’t always work on the first attempt. Try refreshing the page and re-entering the code.