Did you want to build your own BLM PCB (either fabbed or on Veroboard)?
If so, it's more than possible but involves some work:
http://www.ucapps.de/mbhp/button_duoled_matrix.pdf
http://www.midibox.org/midibox_seq_blm_ext/
But if you have the PCB already, you have everything you need to make it work, the SRIO chain is onboard via SMDs.