You can probably get a bit more out of #9 but pressures are going to rise when shooting in higher temperatures, so go cautiously if you increase the charge. H110/ or WW296 will take you to 1450 fps very comfortably, and have safe pressures in temperatures up to 100 deg F.
Please keep in mind that LBT lube is superior to any other I know of in handling pressure. If the gun will handle it, which Ruger revolvers aren't intended too, 60,000 psi will not strain this lube. But, if you were to ever switch lubricants, BACK DOWN ON THE POWDER CHARGE TILL YOU ARE SURE WHAT THE LUBE WILL HANDLE! With most lubricants, that load which performs so well with LBT lube will blow primers and cause severe leading, especially at higher temperatures. Life is easiest for bullet lubricants at low temperatures.