Midi helper doo-dads have become increasingly hard to find. Miidi Solutions seem to be the only ones makiing them anymore so they can ask whatever they think a desperate midi enthusiast will pay.
The only way that I've found is to get lucky on eBay or Craig's List, and the trick is not to just search 'midi A/B box' and give up because what you're looking for could be listed a hundred different ways.
Also, you don't say what you want to do with it, but I bet with the flexibility of midi there's some kind of workaround that would put you in business right away.
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