Richard, many thanks for posting the pic here for us, very much appreciated.
Dinko, have I dug out the wrong box from my spares, it seems you suggest that the pic is of the top of the Clutch master cyl... ? If so sincere apologies, though the cyl shape on the label seems to look like the dual circuit m/c, minus the reservoir.
If this is not the brake m/cyl, happy to go and rummage around in the garage as I am pretty sure I bought spares for all the seals circa 2002. and carried them on our Southern European jaunts..
Quite how servicable those rubbers might be now after circa 20 years sitting in a box...Hmm..?