I have one gallon of unopened high quality tung oil from the Real Milk Paint company. It is called "Half and Half", which refers to the fact that it is a premixed solution of Pure Tung Oil and Citrus Solvent. No mixing required. Totally non-toxic.
It has been kept indoors - never exposed to extreme heat or cold. Sells new on Amazon for $65.
Pickup also available in White River Junction.