I got this "rifle" from a customer of our recycling facility. It's modeled after the "springfield" M1903 rifle and the bolt functions and you "snap" the trigger.
I've heard it's rare to see one in such good shape because they are very light weight and were used by countless troops for boot camp/ close order drill training.
I have no idea if the sling is USGI...
As a kid, I would have killed for a toy gun like this!