Necessity is the mother of invention mate! Sanding sealer works great, BTW, its also just a kind of lacquer.
After many years I still have an oversupply of beautiful, lightweight tissue. It's origins? It was used to manufacture tea bags from! Can't tell the difference between it and 000 Silkspan in practical applications. The price was right too- free! I've even heard of a guy who used shoe box tissue to cover a model.
There's another alternative to Dope which is safe to ship: Deluxe materials Ezy Dope. It's a water based resin that smells of Ammonia.
PS: Since I'm in the mood for some armchair modeling, and for purely scientific purposes, see, I dissected a Lipton tea bag!
What you get is a piece of tissue about 6" x 3 1/4", with a definite lengthwise grain. So I photographed the tissue in comparison to some 00 Silkspan (heavier but the only Silkspan I have).... Notice any difference?
You may want to start drinking Beer in stead of Tea