Having had a good look at the photos (particularly those of the bases and the stoppers) I'm inclined to say that they were made between the wars. The stoppers look to be of very high quality, and even if the bottles were machine made, some care was taken in their finishing.
I think they were part of a large set made for a dispensing chemist - or possibly a doctor who made up his own prescriptions - some time in the thirties. The lettering points to their being 20th century, and shortly after the war we had the NHS, and very few doctors were dispensing their own prescriptions; also fewer pharmacists were actually making the prescriptions up on their own premises (though a pharmacist friend told me she was taught at pharmacy school how to make pills - and that was barely twenty years ago)