We looked at portable drill stands here. For those that cannot afford the Wabeco, which looked like the best of the bunch, UK-based woodworker and timber framer Francis Barnett shows you his DIY rig:

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Of course, it does require you to find a drill with that lathe attachment, or make such an attachment yourself, which could be a considerable undertaking.

Which gives me a thought, for you tool-minded design entrepreneurs out there: I bet if you targeted a fertile market—say, woodworking hobbyists who buy Festool—then 3D scanned their more popular drills, and 3D-printed an adapter allowing it to ride parallel on a jig of your own design, you'd probably do well.