Well, since you're probably "vintage" with a bare cupboard, I'll throw you a bone.
You can usually get pretty close by focusing in on only what's panned dead center then adding a high-pass to remove drums and bass. In rare occasions, you can sometimes find the song out in the internet wasteland already separated into tracks (about 1 in a 10,000 chance - lol!), then you simply mute the non-vocal tracks naturally.
If there's a plug-in to do this, I don't know what it is, but Bapu might - he has ALL the plug-ins.
(Oh, and welcome to the forums!
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