This way requires no smash moves until the last hit with the bat. Choose Ice Climbers and do a Forward + A attack to pin the sadbag down. If it flies, restart. Now do a strong (not smash) Up + A, if it flies high then restart. Now press B as it lands, do another strong Up + A. Pin it down one last time and swing. It should go over 450m/1450ft to get you the Paper Mario trophy.