DS3 Suspension Top mount replacements costs

[DSportRED]

Hi new to forum.     DS DSport Diesel , 2012, 80000 miles.    Car developed noises / squeeks from front suspension R/H side and has been diagnosed  as needing a new top mount.  Local Citreon dealer has quoted £500 to replace ( Including parts,labour and Vat) .    Seems expensive .  Any thoughts ?