Here's the oldest Nd:YAG laser I've found, just added to the collection. It's a c1967 TRG model 104A head, shown here on a vintage adjustable base. Introduced in '64 with a ruby inside, it had an output of 3 Joules. The 1967 Laser Focus Buyer's Guide shows it with the Q-switch option and power supply in an ad that also mentions the YAG option, so that's the date I'm giving it. Looks like it spent some time outdoors from the condition of the nickel plating, but the insides are as clean as a hound's tooth.