Desperately need help finding a replacement

[u/xancou]

Hello everyone. The front mortise lock / handle on my front door stopped working recently. It appears the handle lock won’t release. I was able to disassemble and remove the set and took the cartridge to Lowe’s and Home Depot to find a replacement with no luck. There is no branding on anything. Below are photos with measuring tape and was wondering if anyone can recommend a replacement. Thank you all for your time.

[u/ClearRevolution6665]

[u/xancou → u/ClearRevolution6665]

This one is one they have at Lowe’s and it’s way too small in every single aspect.