ABS Speed Sensor Part #?

[MORS6]

Hi all,
I was needing the part # for the Rear Driver side (left) abs speed sensor.
I've found a few using google on different sites but when I use those site's part compatibility checker they say not for 2003 RS6.
Any help would be greatly appreciated.

[hahnmgh63]

It's either:
13C 4B0927807S
speed sensor / F >> 4B-4-900 476*
left rear /
or:
(13C) 4B0927807P
speed sensor / F 4B-4-900 477>>*
left rear /

[MORS6]

Thanks for the help. It looks to be a tough part to find at a good price.