Leaf bag costume:
Dark glasses, sandals, volleyball. Instant nudist. Carry your suntan lotion in a pouch to cover your naughty bits.
I’ve used that sort of thing:
Being a party held on Halloween, I went home like that, too. On public transportation. The trick-or-treaters in my neighborhood loved it, when they got done screaming. 
Body stocking close to your skin color. Big black rectangle with the word “censored” over your naughty bits.
Does your husband have facial hair, or is he willing to grow some? Grow a goatee (or shave existing facial into one). Either pick up a bald cap or shave his head. Put on glasses, khakis, and a button down shirt and go as Walter White. Maybe pick up a “Heisenberg” hat as well. When people ask who he’s supposed to be he can say, coldly, “You know. Say my name.”
If you look like someone it doesn’t take much to convey that. I went to a party once as Fidel Castro. I already had the beard, I borrowed a green Army Captain’s hat, put on an old shirt that had the sleeves cut off, stuck a big story in my mouth and everybody got it right away.
For an even simpler costume I made myself a punk rocker. Just put some crap in my hair to make a spiky Mohawk and stuck a safety pin through my cheek.
He meant stogie.
I’m sorry, what … ?
Right. Autocorrect. Missed that.
Truth time, I used a piece of band-aid to hold it on. A couple of tiny drops of fake blood made it look very real. A lot of people thought I actually did pierce my cheek and it seems I forgot to reveal what I did. I was contemplating doing it for real but faking it worked well enough.
Thought of a possible costume: Oliver and Lisa Douglas from Green Acres. Husband could wear some kind of dark pants, jacket, and tie, with some bits of hay stuck on. I could wear plaid shirt and jeans, with some big ridiculous rhinestones and a blonde wig. The wig’s the only hard part, but my daughter may have something like that around.
Yes, inspiration struck while I was watching TV last night!
You’d need a red vest and a pitchfork for Oliver. Lisa would be better in a flowing négligée, with a spatula in her hand (for making hotcakes, dahling).
If you have a cat or a dog, put a pig-snout mask on him and bring him along as Arnold “the pig” Ziffel. You need Arnold to sell Green Acres.
Better yet: Buy a ham, stick an “Arnold” label on it, and carry it around with you. You can dine on it for All Saints’ Day.
If you have a friend with a Floyd R Turbo outfit, bring him along as Ebb.
Y’all are trying to make this too good! 
Make big paper mache ham and you can be Scout from To Kill a Mockingbird.
My god. If not for the discomfort of wearing such a costume, I would do that in a heartbeat. I love it! And husband could be Atticus or Boo Radley, whichever.
Gilligan and the Skipper isn’t too hard to achieve with a fishing hat and a captain’s hat.
Go to an Army/Navy store and buy some khakis, a black tie, and a set of US Army Transportation Corps collar insignia.* Let your husband wear those and make yourself up as a zombie.
Voilà! You are now Commander Crane and the Monster of the Week from Voyage to the Bottom of the Sea!
*Yes, that’s what they wore on the show.
Mary Ann should be easy enough to do.