Yeah, that's a tough one. Where I live, I have the same issue with boots. Couldn't try them on, had to order them. So I would order 5 or 6 different ones and try them on the carpet and send the ones that did not work back.
Not sure that's financially feasible with the kinds of bino's we are talking about! But maybe you could research and pick the top 2, then order them in and compare them to what you have now and make a decision that way.
One thing to also consider is the ballistics package. Sig and Leica have AB. Revic has their own. Vortex now runs their own package, Geo Ballistics. The tract has Eagleman ballistics. Not sure what Zeiss has. To add, I think Leica may have a limited version of AB that you have to pay extra to upgrade to get the whole package, but not sure on that. Point is, figure out what ballistics package you are getting from the contenders and if you have a desired package that you like, that might help you narrow your choices a bit.
Combined with other quirks or perks that each have, you might find yourself narrowed to a couple suitable choices, then just order them in and send back the loser.