The C-Speed calc is showing 11.9:1 but 12.2:1 with a two layer. Another calculator using comp height in the formula, says 11.86 with PR-3
With P-30 pistons and a two layer you are 12.5:1
Getting to that area where 93 octane starts letting you down, but with the big sticks, you should be able to keep your timing reasonable and not have to drown it in fuel.
If you don't want to live with the challenges, though, the smart thing is go with the lower compression and a bit less cam. Type R, stage 1 and stage 2 cams on your particular build are pretty well proven.