How about getting him a vinyl record of his favorite alternative/indie rock band or artist? You could also consider concert tickets for a band he's been wanting to see live or a subscription to a music streaming service so that he can listen to all of his favorite artists on the go. Another idea could be a personalized playlist or mixtape with all of his favorite alternative/indie rock songs that remind him of your relationship. Additionally, you could get him a graphic tee or hoodie featuring his favorite band or artist.
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.