I use bar oil, mostly from TSC when on sale for about $6/gal. Sometimes I grab a gallon at the saw shop because I like the guy, his dog, and his shop, costs more like $9/gallon, but he will look at a saw I don't think is running right, apply his magic screw drivers to adjust carb, and share a cup of coffee, no charge.
But, back to the original question: I carry a quart in my saw box, using a very old (more than 30 years) squeeze bottle that I refill from the gallons in the relative warmth of my garage before I head out. I am not a volume sawing guy, I've never sawed more than quart of bar oil in one day in my life. I like the squeeze bottle, I never spill, and if I let it get too full, I can suck a tad out with this bottle.
Side note, I used to pull a wagon with saw, tools, and toddler daughter into the woods. One time I turned around to see my daughter holding my bar oil bottle up for a sip like her milk bottle. She is now 33 and still showing no ill effects from this extra lubrication. (Probably good my wife doesn't read this - I may be banned from taking my Grandson along with me now.)