I use hobbyweld, very convenient with a supply nearby there bottles have a refundable deposit. A few things to consider … your insurer may state butane is for indoor use whereas a SLT runs on propane. More people are now using oxygen generators/concentrators. I suppose cost-effective if you are using a lot. I would love one, but not sure of their reliability if unused for a while. Maybe somebody with experience could advise on the pros and cons of them. Worthwhile purchasing spray leak detector when using oxygen as leaks are odourless. It’s worth decompressing and bleeding regulators and oxygen hose lines when not in use, I once had a new oxygen regulator fail after about 18 months it started leaking from an unserviceable seam. Oxygen bottles are narrow and prone to falling over, so worth tethering to a sturdy table leg or bracket to prevent the inevitable … Good luck with it … Nick.