Look in the "costume" section for commercial pattern brands like Simplicity, McCall's, or Butterick. That's the only way you'll generally find decent men's patterns other than generic slacks, pajamas, and the exact same button-up shirt.
Brands like Burda offer more variety in their regular menswear patterns. If you are thin and/or short, Burda patterns will also give you a starting point that's more likely to fit you better.
Just look for a pattern for a trench coat or something similar, and don't attach the sleeves.
FF9 cosplay? Hit me up!
2014: Anime Los Angeles, Anime Conji, and whatever else falls into my lap
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