Good that you (apparently) have the original power supply with it!
With some more detailed pictures it would not be hard to figure out how to hook it up for a test fire. No idea if it will still run after 30 years, but i certainly is possible for these lasers to survive that long.
One important thing: do not plug in the power supply and start messing around! Though the amount of power supplied is fairly low, it comes at 1 to 2 kV with a starting pulse that could exceed 10 kV. Current on this size model is not enough to kill you instantly or anything like that, but it would deliver a very nasty shock if you got your fingers between the power supply output, possibly even through clothing or gloves when the start pulse fires.