There is nothing wrong with the "proper" Indian Army specification No5 Bayonets. Ditto with their SLR and No9 bayonets. They tend to be longer than the Britishicon spec.
These Snide No5 bayonets on sale on various USAicon web sites for about USD45- 65 are rubbish. Unscruplus dealers are trying to pass them off as the real ones for £150+ in the UK. It's a hard hit when you spend £150 on an exhibit and find out it's worthless! That is why I am flagging the issue up.
I can't bottom out the 2BA screw issue. The two scabbards that I repaired are now living in Southern Ireland, members of a shooting club purchased some No9 bayonets from me. I was not saying you were wrong. It was just the parts I used to mend the scabbards. Of course it's better to use the correct parts if you have them. Which I did not.