Welcome aboard THE premier forum for these machines! You can find just about anything you need to know within the forum.
From the looks of it, it would be a very exciting candidate for a restoration! Much of the surface rust/grime and dried rubber bits can probably be scrubbed up nicely, although replacing the rubber hoses and grommets etc. would likely be the best.
It's hard to see if there is any rust in the critical areas, like the under carriage/swing arm, etc.
If the motor turns freely clockwise via the 17mm crankshaft bolt (under a 17mm cover at the bottom of the front of the engine) then it shouldn't be too hard to get the thing to run, with help from the many articles and tip in the WIKI linked below. It also has the free-to-download factory service manual, with appropriate year/model addendums.
And the members here have tons of tips for tricks to get it spiffed up and riding again, should you desire.
I can't fathom who would toss aside a bike with only 300 miles on it. Checking wear items like foot peg rubber, shifter pedal rubber, and hand grips for wear can help determine if the odometer has rolled over.
Ask away in the various forum sections, you will find many ideas.
Joel in the Couve