Carnivoras in Port Hope is where I go for good profit on around that level.
On your level you should be able to make a couple of hundred k:s profit there per hour. From my experience that is a really good profit place for mages 250~.
I've met people there between level 250 and 600.
The exp is not very good though, so if you go there it's primarily for the good profit and 125 charm points.
Access needed from The Dream Courts Quest and Threatened Dreams needs to be completed.