I could probably have a bunch of PCBs made up for that price, the board doesn't look very complex. $15 is pretty reasonable, this is really not an urgent matter but it would be nice to make use of that m7957 that I have in my pdp-11/23+ eventually. I am just slowly learning how to use the different operating systems right now. I will keep an eye on ebay if one of these goes up again for a reasonable price.
Judging by the schematics, the berg connector pinout is the same.
70-19964-00 Bulkhead Breakout Panel - A B - P1-2 P1-3 - C D - P1-20 P1-22 - E F - P1-25 P1-4 - H J - P1-5 P1-7 - K L - P1-8 - M N - P2-2 P2-3 - P R - P2-20 P2-22 - S T - P2-25 P2-4 - U V - P2-5 P2-7 - W X - P2-8 P3-8 - Y Z - P3-7 P3-5 - AA BB - P3-4 P3-25 - CC DD - P3-22 P3-20 - EE FF - P3-3 P3-2 - HH JJ - P4-8 - KK LL - P4-7 P4-5 - MM NN - P4-4 P4-25 - PP RR - P4-22 P4-20 - SS TT - P4-3 P4-2 - UU VV - P1, P2, P3, P4 - Pin 1 - Connected to panel metal frame and connector shells P1, P2, P3, P4 - Pin 7 - Connected to Berg Pins A, K, M, W, Z, JJ, LL, VV P1, P2, P3, P4 - Pins 6, 11, 12, 15, 17, 24 - Populated but not connected
So if an H3173-A distribution panel was used with a DZV11, and something connected to the H3173-A distribution panel was driving the DSR inputs, its drivers would have to be able to handle driving its DSR outputs when they were connected to ground. Maybe most RS-232 drivers can probably handle that. And if nothing was connected to the DSR inputs on the H3173-A distribution panel, then it would be a non-issue.