Satnav display for an X5 2003 model

[Peterford27]

Hi,
Can anyone offer advice?
I have an X5 2003 with the satnav display losing some of its graphite on the display. I have contacted a BMW dealer in New South Wales Australia who has quoted $5750 for the unit!
I have done some research on the net and have come across a supplier from china that can provide a similar unit that would fit for about USD425. A much cheaper and upgraded option. I have attached the doc for your review.

LS-8868Bitmap BMW M5（1995-2003),E39（1995-2003),E53（2000-2007）Bitmap 7" Built in Canbus Built in GPS/TV tuner Blue tooth/USB/I-pod Double SD Card slot SD Card with map + $10 Built-in DVB-T+ US$40 ISDB-T:+USD40 Car Camera:+USD22 Parking Sensor (4 Sensor):+USD19 TMC:+USD20 Your Car With Monitor:+5m Cable(51~100)pcs: $405 (10~50pcs): $415 (1~9pcs): $425