if you have a 9wt rod, it should be able to handle between 230-250 grains of line for overhead casting. the aftma rates lines by weighing the first 30ft, so your 9 wt line should fall within that grain window. but bear in mind that's all for overhead casting.
if you intend to cast a different way, ie: water borne/sustained anchor or touch and go style of casting, then the grain window can be increased. by way of example, i cast a 540 grains line on my 13 ft 7wt 2-handed rod, and i usually slip on about 140 grains of sinktip to the end. but that's for sustained anchor casting. when i use the rod for lighter flies with touch-and-go style of casting, i use a 480 grain line that's a bit longer.
anyhoo.... to answer your question... yes, you can slip on the sinktip. but if attempt to cast the full line and sinktip overhead, your rod might collapse on you. although, you can also compensate by pulling in more of your fly line and have, say, only 20ft out with the sinktip, instead of the full line, and you would be able to cast that without overloading your rod. you'll have to experiment a bit to find the sweet spot where the right length of line should be. then use a marker to mark the line and you're good to go.
but, you have to bear in mind that in order to get proper turnover, the line has to have more mass than the sinktip or the loop could be ugly and dump before it has a chance to fully turn over. but looking at the sinktip you're eyeing, i think you'll be fine as it's a pretty light sinktip.
hope that helps, and i didn't confuse you even further.