'Pith helmet' advice sought

[Chacal]

I could use some help regarding this 'pith helmet' I picked up some years ago. As can be seen it has had a hard life (in fairness most of the damage occurred before I bought it), but at least it hasn't been otherwise messed around with. I would be grateful for advice on:

a) What is its proper title (other than pith or sun helmet)?

b) In this condition what would it be worth?

Once I have a bit more info, and when the festive season is out of the way, it will be available for sale or exchange.

Thanks for looking

Graham