Sku's don't match the sitemap or the imageshack files anymore, so that makes it difficult. If it was one of the last things you ordered from there you can log in to your trippytips.com account and click on my account, on the bottom right hand corner there is a box that says My Orders, Last Items Ordered. And it should list the things that were in your last order. Click on the name of what you ordered there and it should take you right to the item page, with photo, of what you ordered.
if that doesn't work then the long way would be to check the description on your order and go through
the sitemap. start with the last page and work your way backwards, checking everything that matches the written description til you find the one with the right picture.