Try proofhouse.com
AR15.com has a good listing.
You must call Colt.
proofhouse.com
1981
1995
1956
1957
about 1960
manufacture date of the python is based on serial number.....................
That Colt python was made in 1969.
That serial number is listed for a Colt python made in 1977 (48301E to 86200E)
Your colt python was made in 1961.