JWBH wrote:
is it possible to propogate mistletoe from a sprig of it please?

Probably not. Commercial mistletoe will be imported and may not like
our conditions or our host species. The berries are often waxed or
otherwise treated to make them look shiny, and may not yet be ripe.

That said, the natural way mistletoe spreads is that the berries are
eaten by birds and the seeds excreted onto tree branches. I believe it
can be encouraged to germinate if a very squishy berry is found and
"squashed" into a small slit in the bark of a tree. I have seen it
done like this by three people, one of whom painted over the mess with
dilute cowpat. All of his took, and a small number of the others did
too. I have since heard that putting a binding over the seed to stop
it falling off is a good idea, but no idea how you do that.
Old-fashioned sticking plaster, perhaps?

I believe you have to be quite specific about the hosts.