I have been through something similar not long ago:
What is wrong with my steering?
My problem was a bit more exposed, but I actually bought the shaft without checking mine first because after reading through the links that Bossman posted and what AuSeeker and others wrote, I was convinced that that is exactly what the problem was. That ended up being the case. No problems with the new shaft and the vehicle rides like new again
There is a link to a cheap original Toyota shaft on eBay in the thread linked above, given they still have any, just in case you will be looking for one. There is also somewhat a diy guide if you decide to fix it yourself.