I'm fairly certain that quince will not pollinate pears - I've checked and double checked on the web and can't find anything about this and I'd have thought that if it worked there'd be something out there.
I'm growing a Concorde pear as an espalier 'fence' along one side of our terrace - it is self-fertile but I hope it will be 'helped' by our neighbour's Conference which is in the right pollination group.
I'm with Verdun, I'd go for a couple of cordons if you don't have room for anything bigger 