unless the ball joints have been abused with a pickle fork at some time
in their history and the rubber boots broken, it's most unlikely they're
seized.  get a second opinion.

as for the belt, yes, the time schedule is 7 years for replacement, but
at only 45k, i'd leave it.

I have heard a lot of people say to wait until you get closer to the
90k mark even though you are at the 7 year mark on the age of the
belt. I haven't heard of anyone breaking the timing belt under the 90k
mileage but it doesn't mean you won't be the first.

My own advice would be drive it another year or two and then get it
done.

Nick