GMC 1500 Sierra, 4.8L.   2001 has fault code p1416, dealer told me the smog air injection system pump is bad is this true? How much is a pump and can the average home mecanic replace it, or do you have to be very skilled?

Optional Information:
2001 GMC Serria 4.8L V8

Already Tried:
Called a few mecanics, after I had the code read.