I just bought volume one complete in nm- condition at a local record shop for $1 mark end down from $10. I'd guess that means they are not worth much unless someone is trying to complete q collection and you have the missing set and they can't find it anywhere else.
Well without seeing it, it sounds from the serial number to be an early 1970's model, this is a reference from the Ludwig site, "At approximately the 750,000 mark in the serial number sequence, Ludwig discontinued the brass Keystone badge and replaced it with the blue and olive parallelogram-shaped badge". The original Ludwig badge was a Brass/gold looking one.
1970
The band was formed in Boston, Massachusetts in 1970
Yeah! Queen were around in the 1970's (Hippie time)!
The cast of Ludwig van Beethoven - 1970 includes: Felix Felton Gabriel Woolf
Ludwig van Beethoven - 1970 was released on: USA: May 1979 (Cleveland International Film Festival)
Adelheid - 1970 is rated/received certificates of: Argentina:Atp
Bibi - 1970 is rated/received certificates of: Belgium:KT
Imago - 1970 is rated/received certificates of: USA:R
Togetherness - 1970 is rated/received certificates of: USA:GP
Zomercarroussel - 1970 is rated/received certificates of: Belgium:KT
Humjoli - 1970 is rated/received certificates of: India:U
Lijmen - 1970 is rated/received certificates of: Netherlands:AL
Dastak - 1970 is rated/received certificates of: India:A
Khilona - 1970 is rated/received certificates of: India:U
The Phynx - 1970 is rated/received certificates of: USA:GP