Got the port diameter figure. It is almost 34mm.
So we could go a variety of ways with this.
If you want to keep this port, we can put longer valves and springs in, and put the roller rocker package on top. You would need to pick out a smaller cam, to go that route. But it would give more power than anything you could get with that big cam and normal rockers.
If you want to keep the big cam, we could just use that, and try to make up a prototype set of Shotgun Rockers for you, to try to get some more lift out of that big cam without getting into the expensive roller rocker package. We have to keep that under .510 lift because of spring bind at lifts more than that with the springs we would use in that application.
Or we could talk about some other options, based on your desires that you would need to tell me.
To reach 7500 rpm, you will need a little bit larger port, and you could use some higher lift to flow what the larger port can provide.
We can talk about how you want to get there.