Looking for sizing help

Hi there looking for some guidance on sizing. I went to my local Red Wings store and unfortunately they didn't have my size and it looks like I'll need to order whichever I go with online. They scanned my feet and I came in as a 6.5E with high arches. The sales associate had me try on a 7.5 in the IR to get a "feel" for the shoes, but they were way too big to really get a sense. I wear a 6.5 in New Balance 574 and 997H and a 6.5 in Blundstones (though they fit better with thick socks).

After doing some digging on this thread, I'm torn between the IR and the Beckman Flatbox. I've seen a good amount of suggestions to size down and I found a pair of Beckmans in a size 6 for a pretty good deal, but there's no returns and I've heard they're a narrower last than the IRs. Any advance is super appreciated!