10.2 : 1 compression 360 at sea level. Options?

Just moved from Denver to Austin Texas, and I'm looking for ideas on what to do with my 10.2:1 static compression 360.

In Denver the engine had no problem running on 89 octane due to the altitude, but I'm assuming I'll have issues here (sea level) running pump gas. I know I could just run race gas, but what octane would I need? What other options do I have? Last choice is adding a head gasket spacer and shooting for closer to 9.5.

Engine info -
Open chamber, milled iron heads. Ported and smoothed sharp edges.
No quench , .039 Felpro head gasket
360 30 over with hypereutectic pistons (SLP-H116CP30).
Comp Magnum 280H camshaft
Engine runs at 180 degrees, but climbs in hot weather while sitting and would probably be a time bomb running 93 octane.
Manual Trans, 3.23 gears.