Rudall Carte & Co Graduate series 80 info?

[woop]

Hello! I was wondering if anyone could help me please. I have just come across an old flute that I acquired during high school. I have tried googling it to get an idea of what it is worth (if anything) but I can't find any information anywhere.

It is a Rudall Carte & Co Graduate series 80 with the serial number: 487746. From what I could find out, the company was taken over in 1950-60s? So it must be older than that. I have read that flutes tend to depreciate in value as they age but from auctions I have seen, the prices they sell for are very variable. I can't compare to any others on ebay as there are none listed.

Any info that could be provided would be much appreciated.

Thanks!