The PD32, was published in Micro Cornucopia number 32, (October/November 1986), page 6.
Supports the 32016. Has 512k bytes of DRAM modules.
It is a complete processor board.
It has no bus interface.
It communicates through an 8-bit back-to-back latch.
This is easy to interface to the ISA bus, or a Z80 bus.
And, I presume, an STEbus or an FTDI USB FIFO module.
It comes with all the PAL equations and software to implement UNIX.
I could not find the DRAM controller chips on eBay, so I presume they are effectively extinct in the wild.
The design could be adapted to use modern SRAM chips. A pair of 512k x 8 bit chips would provide double the original RAM.
The byte-wide communications interface could be adapted to use Jonathon Harston's single-channel Tube API, and thus allow Acorn PANOS to run. But that's a job for people with more time than me.