If it's for a prop, you can also find real violins that are unplayable for one reason or another for next to nothing at junk stores, flea markets etc. Generally referred to as "wall hangers".
Heck there are even new Chinese made violins that actually play (although they sound like someone skinning a cat) that sell new for under $100.
I'm painfully aware of this because I used to work in a music store. See, just about every cheap fiddle ever made has the name "Stradivarius" printed or stamped in it somewhere. Right next to the words "copy of" in 2 pt Flyspeck Sans.
Not a week went by that some clown didn't come into the store breathless, confident that they'd just scored a million dollar heirloom for $20 at the swap-n-shop.
It was always a fun break from listening to the endless renditions of "Enter Sandman" to set them straight.
Joe