Ah, I forgot that GV does weird things as you go up (or down, depending on your perspective) in size.
You might take a look at Epaulet's shirts - their sleeves are on the longer side and they offer a simple/easy awesomely priced MTO too (which I'd have to use to get shorter arms!) if you wanted even longer.
But like the TS guys said, just order a size or two and return it if it doesn't work. I can vouch for the materials, construction, and overall fit!
Thank you for a genuine reply.