Isn't there a famous episode of friends where they end up singing the Lion sleeps tonight? Could you get a cheap DVD of that?
Or make the phrase they are trying to get 'the Lion sleeps tonight' because that will then make the film obvious.
You could get a nice box or tin that could be desk/home storage, save a bit of budget for putting a lion bar in it, tucked up under a bit of jey cloth/blanket, and with a folded tissue/pillow, and maybe a do not disturb sign on the outside.
If you think they wont' get it, blu tack some removable 'jungle' clip art type images like a tree or monkey round the inside of the tin, around the sleeping lion. Or put a tiny note/sign saying 'in the jungle' somewhere hard to find - perhaps tape two bars together and hide that note between them, they can open if extra clue needed.
That way they have a lion bar or two to eat, and a nice tin or storage box to keep and use.
Or, get a lynx Africa set as someone said, and sellotape a lion bar to the front, just make a little crown with gold pen and a bit of paper and tape it round the bar. A lion bar with a crown on...they will get that fast I think!
OR, put said lion bar (with or without crown!) in a mug bought from on of the save the lions charities, like this one (this one may not be cheapest/quickest to arrive, but would be nice to get one where the charity benefits). www.cafepress.com/lionalert.559705214