I've flown with neon and argon tubes before. They should be fine, but be careful as baggage handling can be pretty violent, even if it has been labeled fragile.
I have been searching the web to no avail for red and yellow paint used to paint tubes for signs. Many beer signs seem to use this paint and I am basically on my last drops of red paint I got from the previous owner. I'm pretty sure its still being made as I think I saw it on a couple newer Chinese signs. and help or direction would be greatly appreciated. If you have some to sell I'll definitely be open to that as well.