Could an oil finished guitar

[-Rhaab]

like the s5470sol be refinished, like a solid color.

[ryanb]

Yes...

[marianozz]

I dont know, ive read that once you oil a piece of wood, it kinda prevents paint from adhering to it properly in the future...

i guess with enough sanding you could get rid of the oil, but, on an S body that may be way too much sanding!

[syxxstring]

Yes, you would probably want to use a primer and sealer system.
Primers would create adhesion and give you a straight and level surface after sanding. The sealer would bond to the primer and lock anything from creeping up through primer and effecting the paint above.
Depending on the color you want you can tint the sealer and clear.
For a flat surface many sealers are hardend and do not require a clear coat.
Your mileage may vary, this is based on the training in custom paints I have gotten from House Of Kolor. Other paint systems may vary in application.