A quick look on fleaBay came up with this one in the states. This one is used but was used on a E90 so you may need to solder pins 7 and 8 together to talk to all the modules on your E53. This is the exact cable I bought and I had to bridge pins 7 and 8. There are some others out there that have a switch on the housing to bridge those pins.
https://www.ebay.com/itm/15395812627...oAAOSwOSpe1wZM
Here is one with the switch in place
https://www.ebay.com/itm/23400215146...wAAOSw~E5gmAns
If you haven't installed the BMW Standard Tools suite, use this link, it explains everything.
https://www.e46fanatics.com/threads/...tools.1274003/