However, I'm not 100% what it is exactly.
I'm happy if it's a sidepull, I'm happy if it's a bridle, but I'm not super into the whole "Pay $$, get SUPRISE!" thing so if someone knows what it is, I'd love to know exactly before I commit to it.
This is the only picture avaliable:
The seller is convinced that it's a "headstall with a leather curb strap attached" but she also has professed to know nothing about English riding (and she thinks this is an English bridle).
It looks like some kind of sidepull to me...