Jason, just bought my 1st can of 6 in 1, and like you I make 1 pizza a week. I generally do not keep any tomato product in the fridge for longer than a week. I suggest freezing in individual containers, one container per pizza. Using the 6 in 1 is going to be a diversion for me as I have only been using San Marzano DOP to this point. We will see.
I was using San Marzano DOP, but recently switched to 6 in 1 and I love it. I get the 12oz cans for $2 and as I said, I get about 3-4 pizzas out of it. With the SM, I was paying $6 a can and getting one pizza per can, plus having to go through the entire process of making the sauce.
The 6 in 1 also don't have citric acid and I use it straight from the can, with a little sugar. It wins hands down for me.
There are canister/jar vacuum sealers. But I have seen sauce last quite awhile placed in a regular 'ol baggie and smooshed up so the air is driven out...give that a try.
I buy the #10 cans and divide into baggies and place all bags into a larger "freezer" bags....I have no problem with "frozen" sauce per say....but if it's convenience you are after then give the squeezed baggie in the frig. a try....
Ya I am freezing three portions at a time. The sauce doesn't seem runny.
Generally I never keep sauce in the fridge longer than five days, but thought maybe there was another trick I may not know of.