In the interest of proper terminology, the word is swage. It's the method by which the rivets are set. The alternative is "bucking" rivets with a gun, rivet set and bucking bar.
It shouldn't cost much to have the rivets swaged. NAPA charged me $1 a swage to put ends on my AC hoses. Although it's a different swager, I can't imagine the labor costs being much different.
