I wish I knew what species it is, but I've found an evergreen Elaeagnus in a nearby
city that has fruited the past two years in January in zone 6. It's not extremely prolific, but more than I've heard reported for ebingei.
I'd say they're definitely worthwhile from seed, just start way more than you have room for, select any that you like, chop and drop the rest. Even if you get no fruit you'll get the nitrogen and
carbon fixation.
peace