The speakers in both my wife’s Punto and mine have the same problem, they sound like crap for the last year. It starts slowly so you move the balance a little to the back of the car but in the end it’s horrible. My wife drives around with one of those JBL sausages and is thrilled about the sound quality. I forgive her because her reference is what you see bellow.
The foam is completely destroyed so I ordered one set of these JVC CS-J1720X speakers. Okay, its not hifi but it’s probably better than the 15 year old original. It fits without changing the hole or mounting holes but hou have to adjust the connector. I took a saw and cut out the mounting bracket from the original speaker, soldered the two wires with connectors from the JVC speaker and it works just fine.
Other options may be the Alpine SXE-1725s. I went for the Kenwood KFC-PS1795. I hope they fit as well because I ordered them here.
The Fiat Punto’s model MKII or mk2 or make 2 where equipped with two different front speakers. The luxurious cars and the sound edition with part number 46755811 and the budget version was 46527914. My wifes car had the budget ones, she has a 1.4 16v 5 door Punto, I have the fancy ones in my Punto 1.9 8v mjtd HGT. You can see the difference below.
You can see how I removed the factory socket on the right speaker. On the left speaker you see the OEM connector.
In the back of the car there are two tiny speakers with part number 46527917. From both cars they where fine.