How serious is a burnt out selinoid in the transmission?

I have a few burnt out selinoids in the transmission of my '89 Honda Prelude SI 2.0 Automatic. It runs fine, but it shifts a little hard, and when it is cold, it takes a while to shift out of first. I am still driving the car. Is this a bad idea? I am going to get it fixed next week. How much could this cost?