I think the Kawi Rouser goes up to 220cc? GUD Motors had a 600cc scooter if I remember correctly but not sure what brand that was. I wouldn't quite call something with a 600cc engine a "scooter" though.
I had a 500cc scooter back home in Vegas. It was a Piaggio MP3-500 and had a nice smooth ride. Loved it and hated to sell it, but didn't ride it enough to justify keeping it. Wishing I had it here as the locking front forks (3 wheels) meant I never had to put my feet down on the pavement, even when stopped.
Kymco do a 125,150,400 and 600cc and all available here in gud motors. A friend of mine owns a 400cc but says it's not so good as the 125cc around town.
Yamaha has the TriCity version of that bike although only in a 125cc. I have seen a couple around town.
The Yamaha TriCity doesn't have locking forks. For me, that was the primary reason I wanted a 3-wheeler. Putting my feet down at a stop light or intersection was uncomfortable.
Both, Honda & Suzuki have scooter models in production up till 650 cc. I suggest you contact the importers to find out which of the models are available here.
You can buy a fairly nice car for the cost of the larger water cooled scooters. If one were to want one of the bigger scooters I would say the SYM GTS/Joymax evo at an honest 250CC gives good value for the cost. If I bought a bigger and much heavier liquid cooled scooter I expect that the parking attendants were going to drop it at some point.
I have been looking for an automatic for the wife with enough oomph for me to ride also. Just saw the Yamaha NMax. 155cc, disk brakes front and back with ABS, fuel injection instead of carb, liquid cooled, and at 14.9 horsepower it has 50% - 75% more than the 115cc and 125cc models from any manufacturer. Price I saw was p118,000 NMAX - Your New Ride in the City
Doesn't look too bad. About 45 Lbs more weight than an average air cooled, not 45 kilos like some of the larger scooters.
ABS is about worthless in this country IMO. My BMW has abs and it does absolutely nothing for dirt/sand on the roads here.