If I understand correctly the rifle is an Ishapore (Crown/GRI and the Z as a suffix).
If it helps - My Ishapore (original build and Ishapore Fr'd) has 5 numbers and a suffix "Y"
Mine are not the best, but they are not too bad. I can think of lots of Enfields I'd rather have but instead of constantly striving for more, sometimes it's good to be satisfied with what one has...