Can't help you there nor can the US / Can aftermarkets. Index says Mountings, Engine Rubber .. but page calls them Engine Rubber Insulators and only shows 1928 / 29 models. Guess the W8A, 22A, 32A ones didn't wear out. If hockey sticks work for roof bows, seems good for engine mounts grin.
Since we invented the 407 which was somewhat copied by Oakland, you would think same mounts but we know each plant did its own thing, like 614 spear handles at Oakland and our own handles at Leaside, and other difference's, so maybe not same mounts as Oakland ? Reg Bent turned a 407 from BC into a 614, he might know. Reg sold all his cars / parts and moved down east.
Where Are You From? Ottawa Ontario Canada
Do You own a car built by Durant? 1932 614 sedan made by Dominion Motors