The stickers with brand & model are too faded to read and the face doesn't even show brand. I imagine a variety were fitted between the factory, dealers and owners but I'm curious if anyone recognizes it as 'original" and can shed light on brand/model?

Well the make seems to be SPEC11
I don't think this is the original radio though
There are however quite a nice selection of Italian and retro radios available and some now have been converted to Bluetooth and Aux inputs but still keeping the original look
LUIGI

Googling "Spec II" suggests it was manufactured by the Japanese company Clarion.

if you want a period replacement , look on catawiki.com

There are loads of AUTOVOX stereo's fitted to fiats in the 60's-late 70's on eBay
luigi

There are some nice posher VOXON ones as well also fitted to fiats
LUIGI

If you want an original radio from a '76 124 I have one that is fully operational. I was planning on changing it out with a modern option sometime....