Fresh air system

Can anyone that has a bottled fresh air system please check their regulator for a manufacturer and part #? I am wanitng to make a system and have been able to find all the parts except i'm not sure what regulator to use. I'll psot a complete list of parts an sources once I've compiled it. Thanks!!!

 

I have a simpson one that i brought for $699, Regulator does not seen to have a brand name on it has the following number k231A on one side and a small white sticker with the number 470555 on the other side. Hope this helps.

 

I built a system a few years ago, i used parts fron Scott Breathing systems, they are the same suppliers the most hazmat and fire dept use for portable safety systems.Was able to get a small aluminum bottle and regulator from a local welding supplier the furnished equipment to the refineries in the area

 

What other systems out there meet sfi and can any that do be used other than Simpson !????? Thanks Mitch