Why yes, there are! http://www.amazon.com/Doctor-Who-Eleventh-Potato-Head/dp/B00E6GNPNS So Doctor Who Mr. Potato Head can fight Dalek Mr. Potato Head. You know, as you do.
What is this? I don't even... And yet I just bought one. This has the feel of one of those things that'll be worth a fortune in a few years. But even if it doesn't, I mean c'mon, look at it!
I don't suppose anyone knows what terrible potato puns they have on the back of the box of the Dalek Potato Head? For example, with the Eleventh Doctor Potato Head they say he is played on TV by "Mash Smith."
Since this is sitting right next to me (it's a Christmas gift for the wife): "Mr. Potato Head becomes the ultimate "Extermi-tator" when he dons the indestructible shell of the dreaded Dalek--the Doctor's "starch" nemesis!" It also shows him saying, "Mash-terminate! Mash-terminate!"