Hi I have and Armstrong Alto flute that I bought second hand in Sydney Australia. It has an expensive tan leather stitched hard case with blue lining and a metal label inside that says "W.T. Armstrong, ELKHART"
The flute head-joint has no markings apart from the number "77" stamped near the joint. The Tenon or barrel of the main flute has the engraving "ARMSTRONG, ELKHART" but no number, on the top of the main body is a number "C 3977" the same number "C 3977" is also engraved on the bottom of the foot joint.
It plays beautifully, my friends call it the whispering giant, I have tried to find out more about this flute but to no avail, any help would be appreciated.