IRN are not always going to speak. I hate to be that broken record, but you shouldn't get a bird with that expectation. Some will end up being great talkers, but you can't bet anything on it
IRN are super cute and I can understand why you would like to add one to your flock. They aren't the loudest parrot in the world or anything, but they do have a crisp contact call.
I hate to promote my own species, but Plumheads are fairly quiet. He only vocalize his song about once a day for a few min..maybe 5 min or so around 1-2pm. Other than that he is a very quiet bird. His contact sounds a little less crisp than IRNs. I work from home though so he is around me most of the time.
Plumheads are a little smaller than cockatiels. They do need a large enclosure however. They need to have room to climb/fly. Very peaceful birds and super gregarious.