There is any seem sealer just called
"seem sealer" it comes in a small white and green bottle, it's about 3 or 4 in. tall. I have used it on my eurekas for years, one can't I have is 15 years old, I have never been wet in that tent, I use the seem sealer about every three years. The bottle has a ball on the top of it when you take the cap off, it is a roll on type applicator.
I used to purchase it at REI
I have heard of people using Thompson water sealer, but it will flake and peel off.
Carl