Best advice for buying a replacement spoke Can you get spokes cut to length for replacement use in run-of-the-mill bikes, e.g. one with an older 26 x 1 3/8  wheel where there is not likely to be a standard size in the 'DT Swiss' range?

Does anyone have any recommendations on how to accurately get the length right? I imagine this is not going to be an instant job in an LBS, does anyone do this mail order (particularly in the UK)?

Do bike shops generally have that tool to put a thread on the end of a cut-to-length spoke or has that gone the way of the buggy whip?
It's worth asking at your LBS. If you've got more than one LBS, try asking them all.  :)

I don't know if most bike shops have it, but I know at least one of my LBSs has a piece of equipment that cuts a spoke and puts a thread on it at the same time. They routinely cut (and thread) spokes to length. From talking with one of their employees, I guess it was a better deal for them than trying to stock a ton of different length spokes.

Rims might be a few fairly standard sizes, but there's a lot of variety in hub flange diameter. Spoke lacing pattern also affects the needed lengths. In other words, even your unusual size might be something they already stock. Or if they've got something that's just a millimeter or two too long, it's probably possible to cut it without putting thread on it and still have a useful spoke.