Very bad idea anti sieze, don't cross thread the new plug and use a torque wrench if you have one when you install. You should be able to install the new plug with just your fingers and then just tighten to specs. There is a reason the new plug striped out the head. I would price out a used or new head before buying a Heli coil set it might just be cheaper. You will need a complete kit for just one plug, not worth the cost.
Totally wrong.
You should not use anti sieze on plugs going into a normal plug hole
However Helicoils are stainless and time serts are high nickel .
Both of these alloys will gall & sieze when used against a high nickel spark plug.
The makers of the inserts recommend using the high temp anti sieze (not the low temp copper one ).
As do car makers on alloy headed engines with inserts fitted from new, you know people with no idea about engineering like Rolls Royce, Ferrari, Jensen, Healey.
Contry to popular belief a spark plug can ground perfectly well using the base & washer ( where fitted ) against the head, it does not need the thread to make a ground contact