Thrust rod bushings - POSS DEALER BULLSH*T??? ADVICE PLS on p2

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Took my 2004 X5 in a month or so ago to replace the expansion tank and in the free courtesy inspection, the tech advised replacing the front thrust rod bushings. What are they and what they do? The dealership wants $695 + tax for parts and labor and $260 for accompanying wheel alignment - are these fair prices? I am in Northern California, if that helps work out if the prices are fair or not.

Ought I to get this done? And if so, get it done at the dealership or an alternative source (please advise)? If the latter, is it something that can be done by an independent non-BMW mechanic? I ask because my father-in-law owns an auto repair shop and if I got the parts, is this something he would be able to do? If yes, how do you get the parts?

Apologies for all the questions but this is my first major expense for the X, I don't know very much about cars and want to get this done cheaper if necessary work and possible, but also done right.