I nearly purchased the Beckman Chukka boots with commando sole a couple of years ago. They run tts; do not size down to your barrie size. Your foot will be in great pain if you do. I can't speak with any confidence about the other Beckman boots and sizing. They seem to be very well-constructed. You should be able to find great prices on line.
Chukka is on a slimmer last (224); the 6" is on the 8.
I'd go with the 8.5, OP. You want them to run roomy.