With normal watches, the straps are usually on a standard attachment, they only differ in one dimension (the width of the strap in the axis parallel to your arm

With normal watches, the straps are usually on a standard attachment, they only differ in one dimension (the width of the strap in the axis parallel to your arm) so you just need to find a strap that fits that dimension. Unclear if Pebble 2 follows that standard but would be worth checking. I'm sure you can find a strap that fits your wrist.