Struts and mounts for 1999 Camry

My girlfriend drives a 99' Camry and has been noticing a knocking sound coming from the front end. I've noticed it too, it's annoying.
She brought it in to get looked at. The mechanic (who her family has been going to for a long time) says her car needs new "struts and mounts" because hers are worn. Car has 130k and it appears they are the original ones. They said it would be $850. Questions are the following:

1. Is that price reasonable or should we look elsewhere? I'm not mechanically inclined enough to do it myself

2. What happens if she waits a while and does nothing? The mechanic said it would just be a nuisance but it's not critical. Is this correct or is there more to worry about?

Thanks!

 

1. seems expensive to me but I do my own work so not sure. look around.
2. correct and of course tire wear, and cornering performance characteristic changes.