No it is not but an Okuma 55 series is a perfect fit for a 300' copper.
Heres my spooling chart for a 300 copper...
Okuma 55 series (Convector, Clarion)
600-800’ of Blood Run 50# braid- backer
300’ Blood Run 45#- copper
35’ of 30# Blood Run Fluorocarbon- leader