Some members have claimed switching to Synthetic Motor Oil freed up their Rings but it took 200-300 miles of driving to get the effect.
In our DIY Section there is instructions on changing the Delivery Valve O-rings on the Fuel Injection Pump if that is where you are leaking. The only special tool needed is the Socket to remov and install the Delivery Valve Holder and a Torque Wrench that goes low enough as there is not so much torque on them.
DIY Repair Links
http://www.peachparts.com/shopforum/diy-links-parts-category/
http://www.peachparts.com/Wikka/DoItYourSelf