I don't think there is a philosophical agreement on what constitutes "individualism", so I won't try to speak to that.

However, for the purpose of this discussion, we are talking about a society's relative tolerance of individuals choosing to live their life the way they wish and a relatively weak emphasis on social conformity.

I'm sure someone has done proper quantitative research on this, but offhand, I think the Netherlands would score pretty high.

P.S. I used "Western standards" to differentiate from developed Asian nations like Japan, Korea, and Singapore which are more conformist.