Managed to sweep up a trio of cards on eBay, including the Z80 card I was holding out for. Got a good price on it, would have paid that much just for the Z80 card alone.
So it's a Z80 card, a Disk II card and.. a mystery card! The D27160 is an EPROM but beyond that I have no idea. There is a two pin connector on the card that resembles the Apple II speaker connector - is it a sound card?