Mercedes-Benz SLK R171 Key Change Case

Hi, all right. Unfortunately, I only found something about the old keys about the SuFu and not about the chrome keys of Mercedes. With both keys unfortunately all keys are broken in some corner and Mercedes itself says that you can’t do anything about it. Instead, I was offered to pay 220€ per new key. So I wondered if you can’t just change the case (eBay = 30€) and have seen a video to upgrade (click). The upgrade should take place from the key here to this key shell Hope someone has already had experience with it and can help me. MfG alex_mlk