I have used new solid copper head gaskets on a block like yours (between .015 up to and around .022 O ring above the decks)with .045 thick gaskets with no issues from SCE before they offered their titan series with the Teflon embossed option around the coolant holes.
At that time they said it would be better to have the receiver groove, especially when above .022 positive on the O ring.
Do you have the head gaskets yet? If not I would order them in .045 thick and exactly the same size as the bore size, maybe .007 to .015 bigger diameter over all