What i would do is simple.
Get a bunch of pics of him, then read up a teeny bit on clothes in his era.
Then you hunt stuff that looks the same as in the pictures.
Hunt in second hand shops, friends wardrobes, your own wardrobe, internet and shops around town.
If you take details very serious, and you are prepared to do some sowing if necessary, you can do a very convincing costume cheap.
Otherwise you could sow the entire thing.
Don't worry, sowing clothes is not uncool, it shows that you have a good 3D sense, and is handy.
I should sow some more.
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