How much to replace and tune timing chain for '97?

I got a quote that for 97 Expedition with roughly 148K miles it would cost like 2500 dollards to replace timing chain, tensionners, along with sevreal gaskets. I could now believe it's that expensive?

Is someone trying to reap me off?

Thanks guys!

is this a quote from the ford dealer?
and yes it does sound kinda high. but at 250$ to change out the spark plugs ( parts&labor) it would'nt surprise me at all.
Rick. Ore