I’d suggest mail ordering a special little pear tree this Spring.  Most often they’re smaller than local nursery trees, thus less expensive to ship.  Study espalier work, then prune it to match your wire heights.  

Bagged or bare root trees from local nurseries can work well, too.  With those, you can choose a tree with plenty of limbs, hopefully near the right place.  They’re often cheaper, but with limited varieties.    

The pre-trained trees have never impressed me.  You’re limited to whatever variety - and whatever wire spacing they’ve used.  

I once had dreams of espaliered trees - across my front yard … until I remembered the deer..  Hope you’re taking them into account.  Pollinizers, too