Yamaha FG-365S

The value will vary widely depending on condition, playability, and where you try to sell it.  It sounds like it's in good condition.  High action (1/8" or higher) is common due to 40+ years of string tension pulling the neck up, which requires a very difficult and expensive neck reset costing about or more than the guitar is worth.  Reverb & eBay will get the most, then CraigsList and Facebook Marketplace.  I'd say $300 to $400, unless the action is really high.