In a forgettable year in Green Bay, Watson has been a revelation. Although Watson did not see much action before week ten, since then, he has emerged as the primary target for Aaron Rodgers, totaling over 400 yards receiving and scoring seven times.
Watson is a rookie this season, so your best bet is to wait for his Prizm and Optic releases. However, if you are looking for something on the market currently, Watson does have a Panini Instant card which shows him in his Packers uniform. Raw copies of this card go for around $15 on eBay.