I just bought an '06 Cayman S with 42,000 miles. After purchase, between the CarFax and a stack of receipts, I was fortunate to be able to assemble a complete service history except for the initial 4 years or so (i.e. warranty period). The 40k service (same as 60k and 80k ROUTINE services as I recall) was done by the shop that did the PPI so I was lucky.
The CarFax indicated original delivery from a dealer in Montgomery AL. I called the dealer's service department and they were able to give me service records for that period. It appears that some Porsche dealers, at least back in that period, did not provide reports of services done to CarFax or AutoCheck. Plus I was able to get additional detail from another service provider where the item listed was "car serviced". So it may be worth a phone call.
BTW, the tab for the major service at an independent shop in Orlando was $1154, which included oil/filter, air filter, cabin air filter, serpentine belt, plugs AND coils. Coils were $300 of that total. As long as engine cover is off for serpentine belt inspection/replacement, preventive water pump replacement would be cost effective.
Best of luck.