Thanks for all the advice.
I ended up running a line from the main utility box to the final destination. It was an easy project except for the crawling under the house. I was lucky to have an available conduit line from the main box to underneath the house. However, crawling under the house and stapling the line to the floor joists was....let's just say I'm still sore.
Pad & 240v shutoff box: not shown is the 120v outlet box to the left.
New platform in attic for new HVAC - all old ductwork is being removed and replaced with insulated duct:
Old HVAC:
