Many tahnks Victor - you were almost right.
I am indebted to Rob Allan who provided the answer, from Ian Thomson:-
"Looks like a German 5-row (Ph. Trayser?) with Old English stopfaces to
please the British market. ROS Database no 4351 is a 2-manual Trayser sold
in Britain by J. J. Hopkinson as the DIAPASON ORGAN. The second expression
stop may be Trayser's version of the Double Expression---not to be compared
with that found on French Art Harmoniums. Just an idea... "http://www.reedsoc.org/Database/scrollfulldetails.asp?regno=4351&ExtraPict=0&Choice=2&Numberofstops=&fs=TRAYSER
From the above link, we learn that Trayser learned his trade with Alexandre, hence, I guess, the similarities.
I was able to visit the church the other day and I've uploaded more pictures to www.thatminidotcom.picturepush.com
Happy to report that the organ is in excellent working condition. The
bellows have been releathered 'recently' but unfortunately a decision was
then taken to also add an electric blower. This was done rather shoddily.
A large, square, white light switch was unsympathetically screwed next to
the treble end of the keyboard, and an inch of the stop jamb face was
removed for the electric cables... It could so easily have been placed out
of site, preserving the original appearance.
The stop with the missing face says '6 Dolce' , and curiously, the Principal
Treble says 8ft, whereas there is no 'Ft' on any of the other stops.
I've never played a two manual harmonium before, although many years ago I
used to play a gorgeous Alexandre (4 ranks from memory), dating back to
around 1860. The coupling worked perfectly and the action was light and
easy. I don't know what mechanism coupled the two manuals, but it was light
as a feather.
The Bourdon was a little milder than I remember the one on the Alexandre
being, but it gave a very pleasing growl, nonetheless.
The electric blower feeds directly in to the reservoir, and since I was able
to play by pumping, with the blower switched off, I should imagine that the
blower could be removed and the organ returned to its original state.