Don't remember originals resembling galvanized metal. I have pieces of a set of original baffles removed by an enterprising soul with a drill. I can find them and gey you metal thickness and possibly create a template to fix the damages set I have and if it turns out like I want, will gladly send to you the outline and proper bend angles for a drop in fit. These will be for original 65 open letter covers.
Keep reminding me as I am not on my game as I once was.
Martin.