June 1984 IIC+ tube

Hi there, I have a well-maintained IIC+ 60W Reverb Combo, I'm the second owner. It has always had this tube in the tube retainer on the inside wall of the cabinet - a spare tube I'm sure. I just sent the chassis in for a pot cleaning and service, so I unpinned the tube to take a look. For all I know it has been there since the amp was built.

It says Mesa STR 12AX7-A. Is it from way back in 1984? It seems to have a triple mica short plate structure. Who made this tube? Would it be an original tube in a 1984 IIC+?

That looks like a Chinese 12ax7. I use them in my c+'s. My first c+ that I bought in 1984 came with Tungsram tubes.

Looks like the early-to-mid 90s era Chinese (8th Gen) tubes. They're great. I use them in all my Mesa amps.