I buy mine online as the local people don't seem to have it. There are a lot of tank sealers out there but when you mention a product like that they seem to go dumb.
One thing I can say is the product is ment to be one time use. But Larry has a quart that he got a while back and as long as you do it in a humidity free environment and seal it back up as soon as you're done it's reusable. Otherwise it makes a big mess because it absorbs the water.
For sloshing around I bought the quart but really a pint should do.
I got my quart of it at my local auto paint supply store. They had to order it but they had it the next day. $45 at least a year ago. That's not a bad price for a pint.
So far I have Done a riding lawn mower tank and 6 motorcycle tanks including Don's super tank. As Don said though you need to put it back in the can and make sure the lid is clean before you press it back on. I didn't do that the last time I did it and I had to cut a hole in the can to get the liquid to poor out. I guess that's a great testament to how well this stuff bonds to metal.
I got mine as a kit from their web site (see link below). It's $48 w/ shipping. I actually got a new tank instead and never used the kit. It's still sealed in the original box. You can have it for $30 w/ shipping.
I order mine direct from POR-15. I also buy quarts, but what I do, on the recommendation of the por-15 rep, I immediately split the quart into mason jars of different sizes after I open it, this way I have been able to save the paint for a long time by only opening the jars when I need some and the lids don't get stuck. I also store these jars in the refrigerator. Let them come back to room temp before using them.
Well, I had called one NAPA store who told me Northern Tool had it(They Don't), An O'Reily store told me, they had never heard of it.
The NAPA in Colfax, said I don't carry any such thing. But Go see Rick at Bird Haven(about 3 miles out of town). That's kind of a grin, we are experiencing flooding in the area and had to drive 12 miles to get to his place and find roads not flooded.
Rick supplies antique and Classic auto Restorers as well as antiques tractors restorers, from all over the Country. He did not have Por 15, but sells KREEM instead.
He said he knew of at least 200 tanks with it in without a problem. So I bought a quart and will give it a go.