Thank you for the kind words. Wheels are factory 2003-2004 Jaguar S-Type R Zeus wheels. Front are 18"x8" p/n 59774 and rear are 18"x9.5" p/n 59775. Tires are standard Jaguar sizes. Front 245x45 and rear are 275x40. Tires on mine are Michelin Pilot Super Sports. I run Jaguar recommended high-speed tire pressures 36psi front and 38psi rear.
ETA You might try Midwest Wheel as a supplier. They also do great wheel refinishing work if needed.