No, you can't use the UriImageProvider for these purposes. If you suppose to use Bing tiles (like BingMapProvider do), then you should inherit your own classes from the TiledProvider and TiledMapSource (http://www.telerik.com/help/silverlight/radmap-howto-custom-provider.html
). If you suppose to show map as Single image of the specified geographical region, then you should inherit your own classes from the ImageProvider and ImageMapSource.
As for the server side (WCF service) it is on your own responsibility to create classes which will call Bing imagery service in order to get tiles or image. You can take a look into the implementation of the BingTileMapSource to get an idea how it should work, but final implementation is on your own and it is outside of the scope of the RadMap support.
the Telerik team
Thank you for being the most amazing .NET community! Your unfailing support is what helps us charge forward! We'd appreciate your vote for Telerik in this year's DevProConnections Awards. We are competing in mind-blowing 20 categories and every vote counts! VOTE for Telerik NOW >>