I also started saving jars from prego and other quart sized jars with sealed lids. I ran out of canning jars this year and a friend said she used salsa jars over and I tried some prego jars and they worked just fine for water bath canning. If you don’t bend the lid in any way when you first open it you’ll be all set. I ran the lids through the dishwasher first to recondition the deal material. Hot water bath would do the same. She has reused jars like this many many times.
oops deal = seal