I have a bunch of 125 cf but also have a few big ones (2 330s and 1 200ish). They are customer owned tanks but have a ring of the Welding suppliers. In my area, you cant buy a new one this size but you can buy one used from someone else.

2 things to know that most don't - What is the difference between an owner tank and a leased tank? A person has a contract and owner doesn't. In my area, a couple big companies bought up the small guys. Air gas will get out a book and look it up and see if its theirs. Although you cant buy a new tank, there are tons of owner tanks on the market and they have no way of knowing since there are no serial numbers recorded on tank swaps. Basically you show up with a tank they will fill it.

The other thing is switching your LWS. They "must" give you a blank ring so you can get it swapped at a different location. Its your tank. In many cases they don't get them often so you have to call and have them hold one for you. I did this with my airgas tanks because their prices was too high. The guy just matched the other place and all was good since the Airgas is 10 min from work so its an easy trip on lunch.

I know you just get yours filled but around here filling on site is rare. Just giving you options that a lot of folks don't know exist. I hear it is different in other locations. This is the way it is here.

The nice thing about 125's are that you can swap them out anywhere regardless of the ring. The big guys are for Argon and O2.