Only available new. https://www.mpcstuff.com/mpc-4000-8-outs-output-expander-ib-48p-ib48p/
Expand the number of outputs in your Akai MPC4000, Z4 or Z8 sampler with the IB48P individual output board expansion. For the Akai MPC 4000 this is the 8 Out Akai factory kit. This is a used good tested part.