The question is what is the pair worth to sell if you spend $325 to fix the one, vs. throw them out?

If the street value is $326 or more fix and sell them and use the $1 towards better speakers.

You cannot discern sound so well that you will hear a difference of a few inches in speaker height. Moving them 2 1/2 feet farther apart might not matter much either. Try anything temporary as a stand before buying anything. You may be able to just toe them out a few degrees from where they are and get a similar result to spacing them that little bit extra.

I’d determine what direction most people will sit and face, probably with the door at their back and put left on the left front and back and right on the right front and back.

If you put two lefts at the front and two rights at the front it won’t be as loud 36 feet away vs. 6 feet away.

That amp is not going to be anywhere near 400 watts in total or per speaker.