Originally Posted by simplesez
Pay the shipping and directly support a small business. Free shipping from wholesalers has spoiled us. Margins are thin in the real world.
I agree with supporting smaller companies BUT when they're charging exuberant shipping costs its a tough choice. Not for me because I will only accept fair shipping costs---there's too many sellers of any one product so shopping around can save money.
I can't speak to how stronger or longer gas struts would work in your application however there are quite a few suppliers and manufacturers with parts close to your existing specs. Doing a Google search for gas struts should find these.
I offer this having searched for gas struts to fit Snap On tool boxes. Those are probably purposely built to a certain size differing from "stock" struts making them almost proprietary to Snap On's boxes---they do carry a higher price due their limited need for any other application.
Other than those you should be able to find something suitable for your use. If nothing else call the OEM and ask about shipping, ask if they're at all flexible with those costs.