I have actually dealt with this seller in the past
and he is very reliable.  From what I understand,
this is a production cel from the commercial.  It
is not the TV version cel.  So I am pretty sure it
is authentic.  Otherwise, he would say so on his
auction (or even if he isn't sure, he would
mention it).  The seller knows pretty well
English.  So if you do have questions about it,
just contact him or have dougin_box contact him.