L78 Hydraulic Roller

[Survivor 69/Z28]

Hello,
I am planning on pulling my motor out in the fall to fix some oil leaks and possibly freshen it up. It's showing a little oil on most of the spark plug threads. The motor has somewhere between 2-3k miles.
The engine was built in 2006 it's a L78 block with a hydraulic roller cam. On the engine dyno it produced 484 HP at 5800 rpm' and a little over 500 ft lbs of torque at 3500 rpm. The motor has its original 291 heads, L78 intake, Holley 4150 750 DP.
My issue is that I have a parts list and a dyno sheet from 2006 from the previous owner but I do not have the compression ratio or cam specs. So this might be kind of waste of time to discuss this until I know those 2 things.

Since the money has already been spent on making this a roller motor. I am wondering if cam technology over the past 10 yrs from when this was built will allow over 500 hp from just a cam swap? I know, without current cam specs this is kind of a dumb question.
Just looking for some advice on creeping what I have to say 525-550 hp while maintaining a stock looking appearance like it is now.
Other than headers of course. The headers are 2" Hookers going into a 3" exhaust system. The car is equipped with a Muncie M20 and 4.11 gears which I plan on going to 3.55's.
No I am not going with a 454 or 427, sticking with what I have. LOL

Or if what I have is pushing it to the limit then that is ok too. The engine currently pulls 16" of vacuum at idle and really runs smooth.
Just seeking more power like every other gear head 😀