If the Mock orange you speak of is the same as mine it wouldn't make good bonsai from what Iv'e seen of them. Not sure about this one though.
But run thru google I got that it is just that - Another common name for this plant is Japanese mockorange because the scent put forth by its blossoms is similar to that of the sweet orange (Citrus sinensis). The small flowers are about 0.5 in (1.3 cm) in diameter and are held in clusters at the branch tips. They are pure white when they emerge from the bud and slowly age to a mellow creamy yellow. They appear in late spring and last for several weeks. Flowers are more noticeable and attractive on the nonvariegated plants thanks to the handsome background of dark green foliage.
Here is the link I checked with - http://www.bing.com/search?q=Pittosporum&FORM=MYMSNA&web=