Thanks for all the input, I am reading it all and taking it onboard, replying is hard because it takes a while for the mod to ok my posts (any idea how I can get approved to post straight away?)

2e0 - thanks for the tip of using plastic in the strap, I will do that. The bag manufacturer has told me that screws or rivets would be best for securing it. I did think of making this piece just cosmetic, but then I can't see how to fix it securely in that case. Any suggestions are welcome.

I2i - one spigot would help keep more strength in the strap, do you think the rivet would hold it tight enough not to rotate though? It is going to clamp the strap in place.

Cheers