Scalia is most definitely an originalist. The totality of his opinions support that description.
By the way, you've taken Scalia's comment completely out of context. Here is the context of what he said.
“The institution that will decide that is the institution least qualified to decide it. We know nothing about the degree of the risk. The executive knows. The Congress knows. We don’t know anything, and we’re going to be the one to decide that question?When Kalb asked if data collected qualifies as "effects" under the 4th Amendment, Scalia said, "I think so."
Historically, Scalia has said - and I'm paraphrasing - that Congress should make clear the intent of its legislation so the Supreme Court can interpret whether or not the law is constitutional instead of what the court thinks Congress intended.
Congress had a duty to explicitly state that the NSA shall not collect the "effects" of American citizens without a proper warrant. When expanding the power of the Executive branch, Congress should do so narrowly. Unspecified scope always leads to broad interpetations.