Wifi greyed out not working and need to replace

I just purchased an ipad mini 2 wifi and 2 days after I got it the wifi stopped working and was greyed out. I tried all the fixes for it with software and lastly I ended up doing a restore to factory and the wifi still did not come on. The device is out of warranty and it is a wifi only unti. How would I go about replacing the broken wifi portion? Is it just a unit or is it actually part of the board it self. I just need some answers I been searching the web and lots on mini 1 but not much on mini 2. Please help. Thanks in advance for any help provided.