Okay lets run some rough numbers, your load is around 250kg. But you should also take the kerb weight (weight of the car) into consideration. An average EV would weight around 1200 kg (motors and battery packs are heavy). So now our total load is around 1500kg and the speed we need to top is 100 miles/hour or 160 km/hr which is a bit tough.
On an average, considering the weight and motor wattage specs of other EV trucks in the market which can provide 100 miles/hr, we can conclude that we need some where around 50W/kg, that is we need 50W of motor power to drive 1kg of load at 100 miles/hr. So for 1500kg we need around 7500 Watts or 75kW. Practically speaking a motor of 60 to 80W should do the trick for you. You can try the Toyota Pirus and Nissan cars motors since they are also of the same rating Again this is just some rough numbers, you also need to consider a lot more factors like battery / motor weight to performance ration and many more also why do you want to use a three phase AC motor?
