Should I get a JP

Hi there,

Certainly for Tokyo, a return ticket Tokyo - Hiroshima is 37,120 yen vs the cost of a 7 day JR Pass which is 29,110yen.

Hiroshima - Osaka is ¥ 10,230 or ¥ 20,460. However if you would visit Tokyo and Osaka within a two week period then you would pay ¥ 57,580 for normal tickets or ¥ 46,390 for a 14 day JR Pass, so going for a 14 day JR Pass could be your best bet. Especially since you could also use it for additional travel.

Hope this helps!
Daniel