Swapping brakes from another car is not terribly difficult. The rotors are the easiest part. The real issue is the caliper. Does the Tiburon have the same mounting point for the caliper? if not, you will need to have a custom mounting bracket machined to center the new larger caliper in the correct position.
If hyundai is like other manufactures in that mounting points are similar if not exactly the same, I would say that using the brakes off a larger hyundai may be a viable option.
If anyone has access to a tiburon and can take some measurements, or plans on visiting a junk yard with a ruler, this could be confirmed or not.
There are lots of options like this within Toyota and Nissan. I cant imagine that hyundai is very different.
The next issue to worry about is brake bias and the master cylinder. If the new larger calipers need more fluid to move the piston(s), then you may need to upgrade to a master cylinder with a larger plunger. This mod can also cause issues for those that have ABS. None of these issues are impossible to deal with but they are things to consider.