The Revell USS United States kit was first released in 1976. It was developed from the earlier Constitution kit which was first released in 1965. They share many parts but not all. United States has a very different transom and other different parts to replicate an additional deckhouse.
In other words, you can't build a Constitution from a United States kit out of the box.
According to Scalemates.com, the last production run for both Revell's Consitution and United States was 2017, released by Revell Germany.
Both kits turn up on eBay from time to time.
Hope this helps.