First Post, help identify

[lgcal20ga]

I found this sworn many, many years ago in my grandmothers attic. My Dad told me he brought it home from Europe at the end of WWII. I did some searching back then, in the library (this was long before the internet) and found a reference book that told me the makers mark was from a British Calvaryman's sworn circa WWI. On the right side of the blade, at the hilt, there are some letters that look like the last three are TER. Can't see what preceded that. I hope you can see the makers mark in the pictures. Any help would be greatly appreciated. The blade is 33.5 inches, fish skin grip. No other markings that I could find. The scabbard has been painted, so any marks on that are covered.

Thanks in advance for any help offered. And no, its not for sale. Been in the family for over sixty years, I think I'll keep it.

Larry