Get a new cable?”
The cheapest thing to do would be to get a new cable. Since you’re only going to be doing it once, it shouldn’t be too bad to just suffer through the bad interface to transfer them over. From the looks of things, your camcorder uses a 4-pin to 6-pin FireWire cable (though the details I found might not be completely accurate – double check with your documentation to make sure before buying a cable). I couldn’t find any Mini DV cassette readers out there that weren’t also camcorders… but that doesn’t mean they don’t exist. Even if I could find one though, it’s unlikely that they would be cheaper than what you’d spend on a new cable. You could find a cable at Ebay, Amazon (see below),