Canadian hallmark help, please?

[brocanteur]

Hello, today my wife found a vintage 14k ring with an unrecognisable hallmark and "CANADA" stamped inside. Can anyone recognise the potential maker? Trouble is, it can read upside down.
eg: ?PSI or (inverted) ISJ?

Would greatly appreciate any help you might offer. Thank you.

 

[Garnetgirl]

It looks to me like there’s another (worn-out) letter before the P or after the J. Maybe an O?
I’m sorry, I know nothing about hallmarks and can’t be of more help to you.

 

[brocanteur]

It looks to me like there’s another (worn-out) letter before the P or after the J. Maybe an O?
I’m sorry, I know nothing about hallmarks and can’t be of more help to you.

Yes, Ive marked it as a ? in the string of letters in my post. I cant make it out, unfortunately.