i payed 200 to get my valve seals done. And I bought TOGA Performance ones. My theory, "if your are going to replace it, replace it with performance."
www.importperformanceparts.net has some good prices.
The valve seals for the D15 16 Valve are $59.00. As long as it has the 16 valve, all the 16 Valve Valve seals that they sell are all the same. You can tell by looking at the part numbers . All the 16 Valve ones are TOGH21-16HP