1969 value guesstimate around $450
Around 1968.
On the butt
I found a Colt diamondback with that serial number made in 1971.
what is the manufacturing date fo a colt diamondback serial number O72239
Diamondback serial # D69679. was mfg'd in 1975. made about 1976
You will need to call Colt to find out.
400 to 600 dollars depending on condition and where you live.
1977
made about 1977
if the diamondback model should be about 1974
Don't know the value, however based on proofhouse.com ,it was made in 1973.
Found a Colt diamondback with serial number D1425, 44 years old, made in 1966.( D1001 - D2599 ) Sorry, could not find P14083.