These white trim parts were painted and the finish eventually flaked off. This kit shares JWB part numbers 13690450 & B327940. You can refresh that old unit with these brand new, old stock, trim parts. This must be installed by a qualified service agent. These were adapted for use by Jacuzzi but actually made by Hans Grohe.
It's from their Axor line and the original part number is 1345645. There is plenty of info out there to research. Check my other listings for more J Dream parts, particularly the mixer valve itself.