I didn't try to do this before using Word XP (which I purchased in 2002), but I expect it was available on even earlier versions.How do you highlight or colour using find/replace? (Does it matter that I'm still using Word 2003?)
Bearing in mind that I'm on a machine whose version of Word is 2013.... In Replace, click on "More >>". At the bottom left, click on Format, which gives you a list of options. 'Highlight' should be the last of these, under 'Style...'. Note that you can use this function to not only set highlights but also to find them.