Where To Buy 'Rust Converter'......in SMALL Quantity ?

[FlaAveo5]

Hey. I am getting some VERY small spots/lines of rust around the drainholes, and starting on the seams on my hatch, on the inside of the hatch. I assume the holes drain out rainwater from the panel if it gets in. Anyway, it is VERY minor, as you can see. I JUST took the pics. I use to have an 'anti rust pen', it looks exactly like touch up paint in the pen form. I looked online and there are all these 'rust converters' in quart/gallon and bigger sizes. but I cant find the pen sized one. I of course dont remember the name of the company that made it, and I hope still makes it. But I dont need a quart, or a spray bottle of this stuff. The pen is perfect, it goes on either with a soft brush, or with a thin 'pin tip', just like touch up paint in a tube does.

Does anyone have this product I am talking about and can tell me where you got it? Or do you recall who makes it and where to find it? It turns rust into that black 'galvanized' metal and stops the rust. Just paint over the new 'metal' and its fixed. I am seeing videos on 'YouTube' with guys using an acid spray, phosphoric acid, to fix there BIG patches of rust.

But it comes in a big spray bottle, and I dont want to spray it all over the paint and my interior, and I only need a tiny amount. That pen i HAD lasted through like 10 cars/trucks, for tiny spots of rust from rocks/door dings. The stuff on 'You Tube' is called 'Rust-Mort'. I looked it up online but cant find it in a small size. This pen size was perfect, so of course it probably isn't made anymore! But I figured I would ask in here and see if anyone has it, or knows where to find it. Thanks all.