71 383 - options

If this was my mill and since you asked the question of what would I do... which is also dependent of the wallet thickness.... with the “budget is the theme” in mind.

I’d use the rpm and 750.
Run a new cam that fits the build goal.
Unless you can identify the cam in there now and it’s OK with you and it’s use. I would look into a new mechanical cam that works with the cars weight/gear/tire and goal, because it is a manual trans car.

If head milling isn’t much for the wallet.... I’d look at no more than a full point increase, which would be a lot! An actual 9.0-1 is very good.

What is your cars weight, rear gear and tire size?