Timber profiles for window frames

A friend has moved into a house which needs lots of attention to the
timber windows (1920's), and he would like to retain the originals
rather than replacing. I imagine some will need replacement timber
members.

I didn't make a note of the timber profiles (I'll look next time
I'm there), but is it easy to buy timber already profiled to make
frames (the openers, at least)? Are they reasonably standard, or
all different?

A google search is difficult to separate out thousands of replacement
wooden windows, although there was one place in Manchester which
kept coming up which does some timber profiles. Somewhere in or
around London would be good if anyone knows of a stockist.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]