Hmm.. well I can tell you that you won't get much for it on ebay at all. I am talking like under $50.
Seeming that it is so old, people tend to shy away from older flutes. It is not a brand that would really be considered very valuable the older it gets.
Your best bet it to try to sell it on www.usedflutes.com
You could ask for $150 for it, but the most you will probably get it about $100.
I have dealt with buying and selling flute for a few years now, just in case you are wondering where I am coming from on this.
If you do list it on www.usedflutes.com unfortunately, you will get a lot of spam and scammers, so I recommend using a throw away email address.
I used to own a Yamaha 581 and loved it also. But I fell in with my current flute and had to sell it.
