25 Escudos Portugal 1977 KM# 607a

I have two similar KM# 607a coins - 25 Escudos Portugal. One 1977 and one 1980. The catalog lists 1980-1986 for this coin.
The 1977 coin is identical to the 1980 one except that it is smaller - it fits inside the rim of the 1980 one.
Could the catalog be wrong? Can someone shed some light on the existence of this coin?

Thanks

  Welcome to the site.  
There is this one below, which is a one-year-only issue in 1977 and it is smaller. Size 26.5mm instead of 28.5mm but it is a commemorative and is KM# 608 so it it that one perhaps?

https://en.numista.com/catalogue/pieces7338.html

 or this one (KM# 607) is 26mm size ...

https://en.numista.com/catalogue/pieces2383.html

  I went to Search then Advanced Search ...

https://en.numista.com/catalogue/index.php?r=&c=&cc=y&cn=y&cj=y&ce=y&cu=y&cat=y&mode=avance&p=1&e=portugal&d=&km=&i=&v=25&m=&a=&t=&dg=&w=&g=

Thanks!
It's the KM# 607
Didn't find it somehow...have to practice more searches...

Thanks again!