Removing it shouldn't be hard, and take a photo and measurements of it (guide here: https://www.tapmagician.co.uk/TMDefault.aspx?98A??? ) and pop it back in until the new ones arrive. Counting splines is not hard - make a tiny ink dot against one, and then count using a sharp...
With the Timco 7.5mm masonry screws the quote Hole diameter - 6.0mm for low density - 6.5mm for high density. https://www.orbitalfasteners.co.uk/...-fix-concrete-screw-zinc-and-yellow-00060tcon The 6mm pilot hole pulled the Mock Tudor timber beams in really well, nice and tight. Rea...