Sweet looking bike there! Looks like it was really well taken care of. I rode one back when they were new and I had one as recently as 5 years ago when I gave it to my son to learn how to ride.
I don't know the exact number of years the 440 LTD was produced by Kawasaki but I think it was in production in that style from 1979 through 1983 or so. The bike was around before this and after this but in different clothes with various modifications. So you'll find some parts fit your model year even though they may fit or be found on pre and post dates of production bikes like the kz400 or later 440's.
It's an older bike though. You should be comfortable wrenching on it yourself and doing the normal maintenance things (for which many parts are readily available - spark plugs, air filter, oil filter, tires, chain (but I don't think the belt is still available as new). Many times you can find random parts on eBay and often even Amazon will have parts.
If you are not "handy" and / or don't see yourself doing your own maintenance and tune ups, you may wish to reconsider. Unless you have spoken with a local bike shop (hopefully one that's been around for years) in advance and they have told you they can work on an 80's motorcycle? My local "motorsports" shop will work on older bikes but usually don't have the parts for it (ie: I supply any parts or the time to complete is a big ? mark).
Good luck. Nice riding motorcycle for your first Kawasaki. I think you'll enjoy the heck out of it!