Sealant quandary

I've spent last few weeks trying to find a good sealant for copper. I generally find people are using things like lacquer or wax as the way of sealing metal for jewellery. And that's where problems begin: someone throws name of some lacquer or something like that and that's it... but does that person know if it's safe for someone to wear item sealed with it? Because if it's safe for roofs, it doesn't necessary means that potential customer won't develop a nasty rush after wearing a piece of jewellery coated with it. Or, there is that great big "renaissance wax camp". Just one problem: waxes, and I assume it's true for the "wax of all waxes" too, tend to melt/soften in higher temperatures and human body gives of heat, after all. So it doesn't seem like a good way of preventing the green discolouration of the skin after wearing copper (and that's my main reason for researching sealants). Also, I recall reading something along those exact lines: that renaissance wax is great for sealing patinas (with the exception of fire patinas, but those are, partially, impossible to seal due to their nature), but doesn't prevent that green staining from developing.

And finally, the most frustrating thing for me: I managed to find three products that are supposed to be safe for wear, long lasting, preventing unwanted oxidisation and without tacky, artificial feel some other lacquers/sealants supposedly give to the piece, and... two of them are, apparently, impossible to find in the UK, and the third is available in a very limited range ( no spray, only liquid form) and expensive to boot. AAAAaaaaaaAAAAAA!!!!!!! I can happily slather some wax on the outside of, for example, pendant, but what about the side that faces the body? Or what about the chain, for that matter? Preventing oxidisation is fine for me, but I don't want my customers turning green ( and, I assume, most of them wouldn't want that either) and waxes apparently don't solve the problem, and good sealants are close to non-existing here. I swear, one more week like that, and I will go maaaaaaaad. Or a least madder than I already am
Ugh, I really needed to vent.

I hope your day is better than mine,
Kasia