The last blue moon was in May 2002, the next is in December 2005.
Each word rhymes with blue subtly reminding the reader of a blue night, or blue moon.
If your jacket isn't meant to become a part of your regular wardrobe - maybe you're shopping for a costume party or just want something to wear once in a blue moon - keep your purchase on the minimal side.
It's just that it isn't very likely going to be something he wants to do more than once in a blue moon.
For a watch with timeless elegance, you might want to consider a Bulova blue moon phase watch.