Don’t go. Later, claim you were The Invisible Man.
Make sure you buy the officer variety, not the EM.
I’ve never been to an Army/Navy store (are those still around?) but wonder if they’ll let just anyone buy military insignia.
Shorts, a clipboard, a whistle and a little creativity on a blank t-shirt and you can be a camp counselor. I’m adding a Camp Crystal Lake hat to mine.
I used to buy them all the time. Lots of people collect them.
And yes, the stores are still around. You might have to search for one that stocks the really good stuff (going back to the '60s, at least).
I did that one year, but you have to carry around a pillow case full of rocks.
C’mon admit it, deep down you want to be Pickle-nose Girl—she’s a dilly of a superhero.
You could check to see if they now make ‘breathable comfort-fit soft-skin’ ham costumes since they are so popular 
I think they can if they carry them. As long they’re not used fraudulently it’s legal for civilians to have them.
Don’t think I didn’t consider it. 
That was my understanding. I can think of many legitimate reasons for a civilian to buy insignia and such.
One year I tied a cereal box around my neck and poked a plastic knife into it. Never got so many groans at a single pun before or since.
Traditionally, when I’m feeling that way, I go to the party naked and wearing roller skates.
I’m dressed as a pull toy.
Black makeup, or that grease smudgy stuff in the Halloween aisle makes for a simple Alice Cooper face. It’s my easy go-to.
I love to tell people about a murder that happened just that day. A man was found killed while eating breakfast, slumped over a bowl of cereal with a knife in his back. The police think he was the victim of a…
I once made a bandolier of empty beer cans and a long ribbon, tied a bandana around my neck, and went as “The Beerslinger”
“Buckskin” clothes, toy rifle, and some empty beer cans, preferably with round holes: The Beerslayer.
Black eyeliner in a heart shape on the tip of your nose, and then 3 or 4 lines across your cheeks.
Voila. Cat costume.
Put on a black shirt & black leggings, and safety-pin a black crew sock to your butt, and whooo! Black cat costume! Total time, approximately two minutes, not including rummaging around for a safety pin.
I once wore a lab coat (a long white shirt would do) with baby Ruth bars pinned all over as Doctor Ruth.
I am not sure if the costume is meant to be scary, but with long hair Frida Kahlo is fairly easy to do. You basically braid and pin your hair and stick in some flower clips, draw on mono-brow and faint 'tache. Wear a long skirt and a shawl. Husband can be Diego. Or Trotski.