I should not post things at 12AM without previewing - what I was trying to get at was that you can control the D70 tethered to a laptop over USB with Nikon Capture. There is a section in the manual about this but I never read those things anyway. I'm pretty sure you can get the images to download directly to hard disk with Nikon Capture - I'm certain you can with gphoto2 on linux.
Granted this means having a laptop next to your slide copier setup, but if the final goal is to get them on a computer anyway... It isn't a cable release, but a single mouse-click several times and there isn't the delay associated with the self-timer method.
There are also knockoff wireless remotes but I've seen the original Nikon one on ebay for all of 1 GBP so I don't think there is any particular reasons for even mild torture.
re: digital cameras not maintaining old standards - USB is a much more powerful standard than the old cable release. Perhaps this is a case where us youngins tease you a little for "getting along there" Roger 😀
Cheers,
-Gautham