well, just got back from my local dive shop. No useful information from them. Was told I couldn’t even get a visual inspection of it because it is too old, and woudl "crush" when diving. I’m not quite sure I believe what I was told as steel tanks shoudl last a while, and during my research found that people are still using them today, mainly as a double setup. The one piece of useful information I got was that the thread count on the valve is the old thread count.