well...if the chart is available on Oricon's website only, i wont take a risk by put it into my website without their permission.
but if it broadcasted on TV or radio or magazines, doesn't it mean they publishing it and let public know it?
unless you do it for comersial aim, it called piracy and infringing. but you do it for information purpose rite? i think that's ok as long as you credit and link them (things like "courtessy of Oricon.com" etc.).
but, ah, dunno anyway. better you ask to other pple who also do it..