I just went through the process of purchasing a similar model NSX with similar mileage myself. For mileage this high I expected either a plethora of maintenance records or a considerable discount to have the missing work done. The previous owner for mine kept record of everything he did including wheel balancing, brake checks, oil changes, etc.
Let me know if you have any questions about my process through purchasing. I know the help I received from others in the community really helped! [email protected]