Yes, there are pretty good proxy items, even if you don't have exactly the same item. If they have wings from chain X in MFP, but you're at chain Y and you know

Yes, there are pretty good proxy items, even if you don't have exactly the same item. If they have wings from chain X in MFP, but you're at chain Y and you know chain X has a bigger order, or bigger wings, estimate and do your best. Use what you know about other comparable items.