I got back the boards for the two DB-19 substitutes, and put them together today. Both versions use pins sticking out of a PCB, and a couple of rectangular LEDs as mechanical guides. Then there's an IDC-20 connector on the other side of the PCB, where you can attach a cable.
Version A is based on a modification of Uniserver's idea, and uses 0.1" header split up into a few unevenly spaced sections. The DB-19 pin spacing is close to 0.1", but not exact, so the header pins end up getting kind of bent. That's not great, but this version is pretty cheap and easy to build.
Version B uses 19 individual D-SUB crimp pins. The spacing is perfect to match the DB-19 female port. But it's kind of a bitch to build this version, since you have to stuff 19 pins one at a time, and use a female port as a jig, and then cut off the crimp section of each pin when you're done. And the crimp pins are a lot more expensive than regular 0.1 inch male header.
Both versions seems to work just fine. I ran a Floppy Emu through some exercises on a couple of different Macs, with both versions of this board. There were no problems, and the connector stayed firmly in the socket.
I think I'm going to make another revision, that's a tweak of the version A shown here. But instead of splitting up the 0.1 inch header as 5-5 and 5-4, I'll split it as 3-4-3 and 3-3-3. That will be slightly more work to assemble, but will result in less pin bending.
Photos below, version A on right, version B on left: