MLS gasket and ARP's in the engine you have now is the best, most obvious option to me. No need for forgies till 400+ imo, as long as you stick to e85.
It's just a head gasket, and it probably wouldn't have happened if you had stuck the higher clamp force bolts in at the start... Manufacturers use stretchy bolts as a fuse against bottom end damage imo.
If you are bothering to rebuild it, I would probably replace the internals and lean on it harder, but that's me.