75! Take a bow, please. Not many are lucky to celebrate their 75th wedding anniversary, so you should be terribly proud of yourselves for being with each other for all those years. The official theme for this year is diamond. I'd urge upon the jewelry again. A ring, a pendant, earrings or simple diamond studs. Awesome, awesome.
An engraved ring could be a great gift for making your hubby feel special. You should be very careful while selecting the words that you wanna engrave on the ring; something that would make your husband feel proud. You may also go for engraved cuff links or a leather wallet.