Found four of these nice Hex Displays at school the other day, what I believe to be the date code says 8631 (The only other text on them is TIL311 and KOREA), so I would assume 31st week of 1986 O0? If so, cool! Any way they are really nice, bright and nicely made, with a clear red casing letting you see the individual leds and the control chip, they seem to go for a pretty penny on ebay as well (200+ for 50 from China). At any rate I though they were cool, and wanted to share them, maybe catch some interesting tidbits about them from the wise bearded electronics guys out there. I was testing them using my arduino and they work fine.
http://www.ti.com/lit/ds/symlink/til311.pdfSorry no pictures, camera is in an unreachable location right now!