Take your turbo charged aircraft to Mani Cortez at Olympic Aviation - he loves Queenairs!!!
From my observation of Phils aviation I'm surprised you only get 650 kg into an Aztec. I would have thought it would be good for a ton at least!
If you bought a 310 it would not be the first in the Phils. There used to be an old straight tail 310 near the Soriano hangar some years ago.
(As an afterthought, there was also a Cessna 195 and a Beech A90 - first edition, no reverse thrust - in the same area.)