He might play it once on a very carefully set up high quality turntable to record it to tape and a digital file. He'll probably be paid well to play it. Collectors are always looking for better sounding copies of these old blues recordings.
Fortunes can be made or lost in rare collectables. It's a tricky business. But watch Antiques Roadshow sometime (my wife likes it). A lot of people find out that an old painting that grandma had hanging in the hallway or an old piece of furniture that's been out in the garage is worth $25,000.
