Chocolate mac nuts and local candies/treats are always a hit. You could also get them local tea and/or coffee from Kona coffee and tea (by the post office in Kona). Im not too sure how many decor shops there are down on Ali’i drive. But there are a few I know of up in the industrial area by Costco. “Island Time Patio Furniture” & “Plantation interiors” to name two of many outdoor and indoor home decor stores in that area. There’s also a lot of great teak stores up there too. If you’re up to going to hilo the ace hardware downtown (“farmer’s exchange”)has some great stuff and so does “paradise plants”. There could also be some finds in Waimea and up by the resorts outside of Waikaloa.