I dunno WS, I've always thought Western saddles needed more 'stuff' than English. Y'all need latigos, girths, all those heavy pads, and most folks use breast collars.
True, this saddle didn't come with stirrup leathers, irons or a girth, but those are rarely included, and a girth should be specific to a particular horse anyway.
It's definitely not a saddleseat saddle. As another poster stated, it looks more like a GP to me than anything else.
OP, hope the tree isn't broken, and you got a fantastic deal.