As I have said in my Handy Handbook for Teaching Newbies (see above for the page) I always have some paper money in my teaching toolbox, which I always take to class. It comes in handy for various board games, betting games and behaviour management for the whole class.
The images are available online, but to save all of us time I have them saved as a PDF so that I, and you, can print the off, photocopy them and cut them out for use in class.
I use the 1 "dollar/pound" note but will upload he higher value notes soon so that you can choose the ones you would like (the lower value notes are just easier to deal with and count for both SS and T.
(Somewhere I have an entire, printable set of monopoly. I shall upload it and make it available for download as soon as I find it. It can then be used for traditional monopoly or customised to make a more ESL specific game).