Hexbus interfacing

Hello, all: I'm researching ways to interface my TI74 to a host PC. TI made a PC interface cable which I've been able to find from a third-party vendor now that IT is out of the CC40/TI74 business. He wants $94 for it. Way too much for my cheap blood. Sensing a homebrew project in the offing, I've been doing some research. I've been able to find the software for the PC but I've found no info on the cable. The cable probably has a Hexbus chip in it, which knowing my luck is no longer available. The Hexbus specifications ("Intelligent Peripheral Bus Controller" dated 9/83) don't reveal a chip number but does indicate the fab -- LSI Logic. Does anyone have any info on the Hexbus silicon? I've spent some time with the FTP archive on Western Horizon Tech's site but I'm coming up empty. Thanks. Rich