My email said you needed more information but not what information.
I found out it was purchased new in 1965 by a member of the Tulsa, Oklahoma orchestra.
Using my resources to look into your inquiry, I was able to find comparable sales that give your Mid century Karl A Dubsek Flugelhorn a current secondary market value of $80 - $160 USD at auction or in a private sale.
I hope this answers your question! If you would like any additional information or have more questions please don’t hesitate to ask!
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