[Garry Shipton (RIP)]

Mark,don't know if this helps.I re-read your post from last July concerning the unit.I do remember dad telling me that while in Sicily/Italy,they supplied the shells to A Battery RCHA from Kingston Ontario.He mentioned that he was always in contact while near the front with my two uncles from that unit,so is seem logical from your input that you're dead on with your synopsis.
Garry