Hi, I had similar problem with my BMW Display Key and found on ebay a company from my home town, that repairs those.
They asked me if i had parking or non-parking version, size of the battery (apparently it is important) and if this remote is still working/connecting to the car.
I had only broken display but the rest looked fine. They told me that they offer brand new original display keys, that are already paired with some car and this cannot be changed but if my electronics is OK, they can swap display, case, buttons, battery, almost everything besides the component that "remembers" the car.
I didn't buy this service via ebay because i had just few KM to drive to them but if someone is interested this link might be helpfull.
https://www.ebay.de/itm/303888070863
IMO 140 euro was a great deal for full repair.
BMW charges nearly 3 times this price and end result is the same.