The fact that it was difficult seems never to have deterred you in any past searching, Paddy. I know that as a direct "beneficiary"!
There is a 6ft extension in that catalogue with would easily due the trick (if "compatible"), and I'm waiting to hear back from their Tech Support folks about whether they think it will be so for the stated voltage/mA criteria.
Thank you, so very much, Paddy . . . and for so many times over the years.
RHP
Added note @ 3:17pm
VERY nice folks at USBFirewire.com. Of course, they're Kansans, so that explains a lot, right gunug? I got 6 ft extension (plus a "ferrite bead" for good measure) for about 15 bucks.