If your hives low on stores, feed, feed, feed NOW while they still take it. As to feeders, FatBeeMan has the best I've ever seen on his site. You can buy from him or just buy the $5 plans. Easy to build. Also what I do is to build up stores as much as possible then add a 2 1/2" spacer on top and add 2 sugar bricks on top of the topbars. Easy to access winter stores. If they are eating sugar bricks, good bet they have no stores left. Very cheap insurance to get hives through winter.
Have a good day.