those are quite heavy old pedals... you'd be happier with something lighter and aluminum or composite.

straightening that steel pedal is not easy, and they tend to get loose at the cage/struts joints, as others have pointed out.
i keep ones in really good shape, but toss ones with rust and loose central tubes...
i've rarely sold any pairs, and only put them on early bikes like raleigh 3 speeds and 70s bike boom bikes.

your biggest obstacle will be straightening that outer strut... it sets the tube compression, and will need to be bent past it's "Straight" shape to be straightened, and correctly set the tube in place, under compression..... which can't really happen with the strut in the pedal assembly...

the ones pictured are in nice shape, though!

leave it alone, try straightening the outer hoop, or get lighter, better one.. your choice.