^^^
If you just want to rent a Ferrari Lambo or Aston Martin, you can also go to Dockx, the car & truck rental company:
http://www.dockx.be/nl/sport_wagens_cabrios_nl.html Though if you rent it for a day it's rather expensive. Maybe you can arrange something for half a day?
On the other hand, if you want to give your dad a present in which he can drive more than one exotic, the road drives of Legend Car are interesting. They always start at Waterloo (not thát far frome where you live). The next one is this weekend, but you'll be too late for that one
The 10th and 11th december, there will also be one. On their website you click on 'stages & planning' and than 'stages route'