This is the most common method for distribution. You can find "Sync keys" on community forums or the The Star Wars Trilogy
Restoring the film was a grueling, years-long labor of love: star wars 4k77 archive
This is a critical point: Team Negative 1 does not sell the files. They do not profit. Instead, they follow a strict preservationist ethos: the files are made available via peer-to-peer networks (torrents) and private file-hosting services for existing owners of the film (under fair-use arguments for preservation). Major studios, including Lucasfilm (now Disney), have historically tolerated such projects as long as they remain non-commercial and do not directly compete with official products. This is the most common method for distribution