You say this as a joke, but saran wrap actually can be a very effective replacement if you can't get your hands on any real condoms. You just gotta make her to double or triple wrap it.
They definitely still make those because a lot of people are allergic to latex used in most condoms. And I know you guys are joking, but Plan B is really unhealthy to use regularly. But if it's some wild one night stand then it serves it's purpose.