Thanks all for the comments and thank you Julie for the links. I will be in touch with Rio about the Harris regulators.
Ted, to answer your questions I use a 5lb propane tank which our insurance company has OK'd for indoor use. The threads are as you noted. Oxygen, I have an account with our supplier for refilling (they pick up and drop off as required) and I also keep a back up B tank. Generally I keep a H size tank (60" tall) as our son is a glass blower and sometimes comes and uses my shop if we are doing something together.
He can burn through a 60" high oxygen cylinder in 2 or 3 hours if he's got that thing cooking.
I have 3 torches that I use, depending on what's happening (not including the glass torches), but it's the Mini midget torch with the small sapphire tip that I have issues. Each torch has it's own hose set and I have a y valve after the flash back arrestors to allow me to have two torches attached to the tanks at any time.
The Oxy cylinder is secured to the wall so it does not fall over and become a missile (for information on this, go back to Hans Meevis really old accounts of his shop in SA burning down and an Oxy cylinder becoming a projectile into his car over 1 km away.)
In terms of industrial suppliers, believe it or not, the jewellery suppliers are much more advanced. I had started talking to the industrial suppliers over 6 months ago, when I knew I was having pressure problems (mostly Oxy). When I open my Oxy regulator (all the way till it stops), the pressure jumps up to 40 lbs, even though it's set at 20. Releasing the pressure before I light the torch brings it down to 20, but it's tough to light a small torch when the pressure keeps climbing. I don't keep my torch lite when I am working, so each time I go to use it, I have to relight. Just irritating. As these regulators are now approaching 10 years old, it's time to replace.
In terms of industrial suppliers, what I found is that they carry 1 stage regulators but can access some 2 stage regulators although they are not common and tend to be ordered in as requested. Most industrial welders are not using the same type of mixed gas control as jewelers are, so they don't need to have the fine flame control as I do. (welders like big flames). When I got a quote for a 2 stage off shore regulator (not Harris) it was over double the price of what I saw the Harris regulators for in the US.
It seems the industrial suppliers in Canada are not prepared to be competitive and don't order enough to make it cost effective. So I will be purchasing through a US supplier and shipping to me. Frankly, all 3 industrial suppliers that I spoke with were not very helpful. And all I have is 3 suppliers in my area. Even my gas supply company didn't know much about 2 stage regulators.
So I think I'm off to call Rio and order the Harris ones!