I currently am looking into this topic as well. What I found is that there are several methods to do so.

You could lower the config on where priviliged ports stop. I am not that deep into linix to be able to tell you if that is secure or not. But somehow that priviliged ports start at 1024 has a reason.

There’s also the possibility to run forward the traffic from port 80 which is a priviliged one to a higher port, but i somehow did not manage to make that work.

If I am correct the higher port would then also route the traffic again trough port 80 so the source of request. Difficult topic. Would love to get a good answer to that problem.