Not sure of the size but they may not necessarily be repros. Apparently, solid brass folding posts were available in Canada for at least the 28 roadster, I have seen a Canadian A era ad that mentioned them. Do they look anything like the attached picture? These are solid brass folding 28 posts believed to be original or at least era accessories, unfortunatly I sold this 28 in 65 so can not take any measurments or provide additional details.