You do not need an external website link for this. The driver is already on your Windows 7 installation.
Driver P47 Bluetooth V4.0 - Windows 7 Compatible. Download Mirror 3 (Slow). p47 wireless headphones driver windows 7 link
Choose as the manufacturer and select Windows Mobile-based device support (even for non-mobile headsets). You do not need an external website link for this
Since direct links change and driver hosting sites update, here is the most reliable current strategy to find the correct on your own: Download Mirror 3 (Slow)
: Visit the Dell Drivers & Downloads page and enter your Service Tag.
Searching preconfigured driver folders...
Since the P47 uses standard Bluetooth profiles, you generally need to update your PC's Bluetooth stack or download a generic driver installer if Windows 7 fails to recognize the device automatically. Generic Driver Installer: You can use a tool like the Bluetooth Driver Installer