LonestarStihl
Addicted to ArboristSite
I'd be looking for a 1990s 50cc saw if you want to do your own work on it.
They make winter grade bar oils. If you cannot locate that try some 20W motor oil, the cheap stuff should work fine.
Concerning a gas saw. A quality 50cc saw from stihl, husky or dolmar should be what you need. Hard to find older ones still in good condition, but much easier to work on if you can get parts
And let’s not forget a good ole McCulloch!