There are lots of inert, teflon based lubricants available, but none of them are as readily available and as inexpensive as ChristoLube.
The only lubricant I can think of that *might* work as a substitute for ChristoLube (in some applications) is Tef-Gel (www.tef-gel.com). It's a teflon based grease used primarily to prevent corrosion between dissimilar metals in the marine environment. I don't know if the manufacturer approves it for oxygen usage, but it appears to be pretty inert. It's very viscous, so it probably isn't suitable or use on internal regulator parts, but it would work OK for lubricating tank o-rings, tank valves, etc. It's available as most marine hardware stores like West Marine.
The only lubricant I can think of that *might* work as a substitute for ChristoLube (in some applications) is Tef-Gel (www.tef-gel.com). It's a teflon based grease used primarily to prevent corrosion between dissimilar metals in the marine environment. I don't know if the manufacturer approves it for oxygen usage, but it appears to be pretty inert. It's very viscous, so it probably isn't suitable or use on internal regulator parts, but it would work OK for lubricating tank o-rings, tank valves, etc. It's available as most marine hardware stores like West Marine.