As you said, budgets not a problem and if you intend to keep the car and pay for the labour involved in taking apart and in and out, then you might as well get it rebuilt with uprated internals. And since the oil pump is basically a motor out job, you might as well spend the couple hundred bucks on doing it, which gives you the option of having 300+kw later on.
Just a word of advice, what an engine build is budgeted to be at the beginning always ends up a couple grand more from my experience, so just budget for that.