hmmm tough to say , i dunno where could be reliable, and to be honest if i had a convert , id look for one at the dealership, its such a rare option , i really have a tough time thinking of who would carry such a an aftermarket product.
you can always browse classifieds for one, even check out some bimmer magazines too see if someone is selling one or there might be an ad that might lead you the right way...
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