Hi and thank you for your question. My name is ***** ***** I will be happy to assist you.
You can purchase a replacement cord from amazon. Here is the link to a cord that is for your device: http://www.amazon.com/NiceTQ-Transfer-Magellan-Roadmate-5230T-LM/dp/B00QNCUD88/ref=sr_1_1?ie=UTF8&qid=1449252548&sr=8-1&keywords=magellan+5045+usb+cable
You do not need to purchase your maps on a MicroSD card since you already have one. 8GB should be plenty to store your map updates on.
To update your maps you would need to connect your device to the computer. Then, if you dont already have one, create an account at MagellanGPS.com and then download a program called Magellan Content Manager from the Magellan website. Once you have a cord to connect to the computer, run content manager and follow the steps for setup. It will scan your device for available updates and allow you to select what updates you would like to install.
When content manager scans your device, it will tell you if your European Maps require updating or not. If they do, you will also be able to update them right from the content manager program.
Here is the link for the Magellan Content Manger: http://www.magellangps.com/contentmanager
I realize you dont have the cord at the moment. When you do get the cord, if for any reason you run into issues during the update, please come back and let us know and we will be happy to guide you through the update process.