bushing

DIY'er here, PVC toilet flange in basement was in very bad shape and could see it was a 4in flange with an inside coupling to waste line, at least that's what it looked like. Chipped out the flange and coupling hoping to duplicate the setup with a new parts. But what's down there is some kind of...

My plumber installed the rough in for my shower head arm too far back in the wall and the shower arm only sticks out of the wall 3 1/2". I would like to increase that length. The rest of the trim is brushed nickel from American Standard and they don't make a longer shower arm in that style...