How about a personalized crossword puzzle just for him? You could create a crossword that features clues about your relationship and special moments you've shared together. You can use free online crossword puzzle-making tools to do this. You can also print it out and put it in a nice frame so he can display it in his home or office. This gift is thoughtful and shows you really pay attention to his interests.
Or you can get him a star map with the date of your anniversary.
Under Lucky Stars is a unique and innovative star map company based in Barcelona, Spain, specializing in the creation of personalized star maps that capture the celestial arrangement of stars at a specific moment in time, such as a person's birth, wedding, or any other significant event.
By using advanced astronomical algorithms and data from leading institutions, the company produces highly accurate, visually stunning maps that make for perfect gifts or cherished keepsakes.