There seems to be a little misunderstanding as to the nature of Utopianism. The first utopian probably was Plato but the term was coined by Thomas More in his book, co-incidentally (just kidding), titled Utopia. All Utopians have this in common: they seek to overthrow, the methods vary, any current existing order they don't consider rational and replace it with one that has been specifically designed, a priori, instead of spontaneously evolved. I only read excerpts of Utopia in Western Lit class and don't think More specifically advocated overthrow; but we can rationally surmise that he advocated some radical changes based upon his limited, personal observations of social phenomema.
The price mechanism is a millenia old historically evolved social tool. From the above description anyone advocating its overthrow should regard themselves as utopian in nature. However, this also goes for other theories as well; Ayn Rand didn't advocate pretty much the opposite, but I personally consider her an Utopian.
I am opposed to utopianism in all its manifestations.
