just a thought: you could always just do a day trip to lamanai instead (about $120/pp). very cool too, many structures, pyramids, jungle & monkeys, etc, its just not tikal, and you would be back to SP in time for dinner.
for easier logistics, save tikal for another Belize trip, combined with a few days in Cayo (beautiful), which is much closer to the border.
just my opinion.