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...I have straightened a couple of frames with mild damage like that. (If it is indeed a little bent.)
The fact that it's basic Carbolite tubing works to your advantage. But it's always an experiment to do so.
The setup is relatively straightforward. Affix a piece of steel plumbing pipe (that is small enough to fit through the head tube races) into a very large and well mounted bench vise.
Turn the frame upside down, slide it onto the plumbing pipe positioned in such a way that it allows you to put a scrap rear hub (or axle ...if you use an axle only it might bend a little) in the dropouts. Then take a lever length of 6-8 feet of 2x4 framing lumber, insert it so it goes on top of the rear hub, and the far end under the lip of your vise workbench. Then pry down until it looks straight.
Leave the head tube races in place or you will ovalize the head tube. Or install other, sacrificial races of steel, if your headset happens to be aluminum alloy.
After you get it to your liking, you need to string up the frame, and check out the frame's side to side alignment, but that usually remains constant. And someone ought to check the fork alignment, if you can.
It's kind of a project, but this one turned out OK.
If it does decide to fail at the bend sometime in the future, it will start as a small crack, which you can watch for. So not at risk of catastrophe to ride one repaired like this.