parse-replace - parse-based REPLACE function (See related posts)

    parse-replace: func [
        {Replaces the search value with the replace value within the target series.}
        target [series!] "Series that is being modified."
        search "Value to be replaced."
        replace "Value to replace with."
        /all "Replace all occurrences."
        /case "Case-sensitive replacement."
        /local len skip-len rule text
    ][
        len: length? form search
        skip-len: length? form replace
        rule: copy [
            [to search mark: (change/part mark replace len) skip-len skip]
            to end
        ]
        if all [insert rule 'any]
        either case [parse/all/case target rule] [parse/all target rule]
        target
    ]