Loki, I didn't mean for my post above to sound harsh, but it probably did. I was in a rush on the way out the door.
Everyone here will support you with help how ever you decide to go. We're trying to get you to adjust your thinking to the size of the car you are building though. Unless you plan on seriously competing on road racing courses that are specifically very hard on brakes ( which would be unusually short and twisty courses, just a few in the country ), unusually large brakes are not needed. If you are willing to go to the effort of buying the stuff you mention you can also choose to build to a reasonably light car. That means it would be well under 1500 lbs., less than half the weight of almost anything you could buy these days.
Since the frame rail in the cockpit is unlikely to even reach the height of your knee, a set of 15" rims will have a nicely tall and modern look on your car. At least I would think so. I'm sure the original had 13" tires...
Also I was genuinely interested in the weight of the parts you are looking at because I am going thru that now on my build. Possibly steel rims at 15-20 lbs. and hub/rotors at a little under 15 lbs.
All this unsprung weight in tires, wheels and rotors, going 0-60 MPH, has to accelerated to 60 MPH, but also spun up to speed. So it all costs twice and can count for 25% or more of the power used on the 0-60 run. It does make a real difference. Plus these parts are more desirable these days so they charge more than they actually cost compared to 15" stuff.
A 225 tire on your car, considering the weight on the rubber will be something like a 650-750 size on a modern sporty coupe these days!