There is no Yoda topper as far as I know, only the Yoda Slurpee cup.
Yoda Slurpee Cup
That's an awfully strange looking cup! Yoda must really be meditating hard...
I just assumed there was a Yoda topper based on starwarsnut's earlier post:
There are four different cup types for the 7-11 Slurpie set. First, there are two different types of Toppers -- Darth Vader Head, and a Yoda Head Topper.
I guess time will tell if this ever shows up.