Just to close the loop on this... I sent an email to Stuart's Services (
HWH Replacement Parts - Stuart's Services) as recommended by Skip426, describing my issue and within 10 minutes had a call back!
He was very helpful on the phone and got me going in the right direction. As it turns out i didn't need any parts or service. Really good company to work with!
It turns out i had a leak from an oil fitting. It was an easy fix to remove the fitting and wrap some teflon tape on the treads and reinstall. However i couldn't get to the fitting without removing the jack and that took me a couple hours.