Ask the service shop if they have a display calibration tool, if not then check with creative agencies (Sign shops, photographers, ad agencies, etc) around your area. If you could "rent" one for 15 minutes you could use it to calibrate your Mac's color profile to bring out true whites and whatnot.
LCDs are all different. I'm still shocked that these types of problems are so often complained about these days. 6 - 7 years ago people just accepted that there were variances and would simply adjust the display's color and go on about their day.
Article that talks about calibrating displays