If your current tyres have 15k on them, they are likely to be factory fit, so you can check the brand.
If you look on the sidewall, you should see a 4 digit code, this shows the year the tyres were manufactured, if the tyres are original, look for (XX07) or even 06 if it's an early 2007 car.
I have seen Dunlops on a car of this age, they definitely need changing, tyres are not at their best after 5 years, less than ideal on a performance vehicle.