That sounds extremely high. I would think around $75.00 a wheel would be more than enough. I just had 4 landcuiser wheels shipping from the midwest to Florida and it was like $150 total for all four.
Go postal service as UPS charges a customs brokerage fee that is pretty steep. FedEx Ground usually is close to postal service but I do not know if they have international shipping nor if they have a brokerage fee. 1 or 2 boxes should not be too terrible as I recently shipped some large boxes of vintage bike parts. Be sure that the parts are spotless with absolutely no dirt anywhere as I've had parts confiscated before that were shipped into the US dirty and UPS was no help whatsoever!