What type of spare key do you want? Do you want a remote key...or will a non-remote key fit the bill since it appears that it may be just sitting in the drawer?
Do you know what type of key the dealership was quoting you for $200...remote or non remote?
The non-remote keys usually cost much less than the remote keys. There's the illuminated key, and the plastic key, and the almost useless VALET key. The gray-head VALET key will not open the glove box or trunk (if you have a trunk lock cylinder). All the other non-remote keys will open EVERYTHING.
If you were quoted the price for a remote key...but you could live with a non-remote key...then call your local dealership back and ask (or give them) the 11 digit part nbr for the non-remote key of your choice:
Not all non remote keys are available for every model...but the illuminated and spare key with plastic blade is usually available for the e53...and the part nbrs may be different if you have the different type of key blade. If you key blade is different than the ones listed...then pull up the diagram in one of the online part databases...and use your X5's VIN so that it will list all of the types of keys available in the part nbr index below the diagram. If an item is "grayed out" in the diagram and/or not listed in the part nbr index...then it means it's not available for your VIN:
{
DO NOT use the BMW part nbrs below...I don't think they are correct for your model/model year...look them up in the part database to get the correct ones for your needs}
If you had a model/model year listed...I could have pulled up the diagram and a direct link to the available keys. But it appears you've been here for approx 3 years...so hopefully you're familiar with some of the online part database sites like
www.realoem.com,
www.bmwfans.info, and
www.etk.cc. Look for the diagram below and see if
#1, #2, or
#3 is available based on your VIN (#2 is the VALET/Service key):