My husband has a pair of Merrell hiking boots that still have a lot of life in them and he would like to get new insoles for the boots.  I purchased insoles for my Oboz hiking boots, both from REI last year, and  that I absolutely love.   My insoles are from with Memory Foam.  I am looking for the best insoles for my husband's Merrell hiking boots and cannot find the same type of insoles online at REI.  Could you assist me with picking out the best pair for  him?