[Arran]

I don't think that there were any issues with the quality of Philco output transformers at the time the model 14 was built, that is if the speaker and transformer are the same ages and type as the one that came with the model 14 to begin with. The really crappy output transformers came out in the 1939-42 models, they were usually mounted under the chassis, it's a rare bird to have a model 40-180 style chassis with a good original output transformer, they either have a replacement or an original with an open primary.
Since it was a console chassis apparently it may have had a 10'' "H" type speaker originally, the table version would have had an 8'' "K" type I think. In my opinion the Hammond output transformers, especially the universal ones are overpriced, by far, over what their competitors have on offer, such as Edcor. In a pinch I would have been inclined to search for a NOS replacement, not necessarily a Philco part but a Thordarson or Stancor, or a used one salvaged from a junk chassis or speaker. The impedance isn't really that hard to change on the output side, the secondary windings are towards the outside, undo a few layers of paper and it will be exposed, ready to alter or rewind if necessary.
Regards
Arran