My all time favourite factory knife for this sort of work was a Schrade Old Timer Sharp Finger, which some thieving scoundrel swiped last year
I think I've just acquired one of those.It says it's a Schrade Old Timer and has a short curved blade.Was in a total state with concrete?!!! on the blade.I'm trying to get an edge on it and clean it up at the same time.I don't think it will be a favourite as the handle feels tiny in my hand but we shall see.
Another thought on the original post: Knifebargains.co.uk have a Mossberg Bird & trout pair in one sheath.A friend has just bought them and they look good if you like Very minimalist design.Pretty sharp out of the box and not expensive I think.Could be worth a look.
Cheers , Simon