I'd be leery of what you'd get back in terms of top wear, most would be alright but somebody might foster some junk on you.........if too tight you can get valve shortened slightly for little cost. I've even done it by hand on a cheap bench grinder, but I made a fixture to hold valve square to the wheel.
You may have access to earlier tappets with shim on top that fit around '98 zetecs, they may directly interchange. You can flip shim for new surface too.
I used to swap shims/tappets on bikes, but some of the parts they put out on counter for swap were garbage to me.