Bit the bullet and ordered some 'phase change' vests made by Polar Products:

http://www.polarproducts.com/polarsh...st-403p197.htm

Best price was here:

http://healthproductsforyou.com/p-29...ling-vest.html

Up until the 15th or 16th, you can use coupon code DAD2014 for an additional extra 10% off,,,

The dang things are pretty pricey,,, sure hope they work!