even if you could bruteforce the eboot and get the correct klicense key or if you could magically find someone who had the correct .rip / .rap files it aint gonna matter speculation is that the eboot is infact a dummy too, just a couple lines of code to let it install the rest of the files.
Once the release date finally comes round, the console would dial into the server to get the real activation .rif files, once done it would unencrypt the PKG EBOOT, see it is a dummy or incomplete then download a new eboot from the sony servers (so day one update 1.01 would need to be downloaded).
It is more realistic for a media disc leak in about 10-14 days time, dont worry if you have the PKG installed you possibly wont have to download the game completely again, just unpack it from the PKG (hopefully you still have it saved on your computer) then FTP it onto your console in a certain directory layout. Grab the PARAM.SFO and EBOOT.BIN from the leaked media disc and FTP them over. Fingers crossed when you start it in your favorite backup manager, you'll be in GTA heaven.
But please just wait for the media leak, trying to bruteforce what you have now is a long shot to get it unlocked and if you were you'd probably find you cant use it.