Well, yes I could, but I wanted to be able to say that I made a full three-piece suit for myself. It's just my sense of crazy.
I made a simple mockup out of muslin, which fit fairly well. I had to do a few alterations, primarily to the sleeves and armscye, which are my primary problem areas.
One of the things that I changed was to have a French cuff instead of a simple sleeve band. This particular cosplay "appears" to have unfolded French cuffs.
The final shirt, sans buttons.