I disagree with db that all Toyota 4-bangers have long had problems with excess oil consumption. I’ve owned a number of them, still own one, and if properly maintained they do not. But, he and I have had this debate before. We’ll never agree, but that isn’t important to you. The only important thing for you is to realize that there are opposing views on this allegation. Do not assume that because you have a Toyota 4-banger you therefore are destined to have excessive oil consumption.
I do agree that your car needs to be looked at by a qualified diagnostician. It is very possible that you have seepage through the valvecover gasket, the oil pan gasket, the crank and/or cam seals. You may also have oil being blown past worn out or gummed up rings and/or cylinders or being drawn past tired old valve stem seals. A clogged PCV valve could also contribute. A quart every 300 miles is excessive, and the best next step is to get an evaluation as to why. None of the aforementioned would be unusual to find, depending on the engine’s history and driving environment. Many are affordably correctable. Worn out cylinders and/or rings aren’t. It’s important to find out which are applicable, as best as a good look-see can tell. Seeping valvecover gaskets and crank/cam seals are easy to diagnose, as is a seeping oil pan gasket. The internal cylinder condition can likely be determined with a simple wet/dry compression test.
Don’t let the lack of smoke in the exhaust fool you. In modern cars, much of the burning oil is caught by the cat converter. Besides that, at idle the lack of a cloud means little. And if the valve stem seals are leaking it may not present except under deceleration.
If it does turn out to be wear, I support the recommendation to just keep adding oil. It’ll probably serve you well for another 10 years.