Need help identifying Portuguese silver maker

[svc]

Hello,
I have Portuguese silver mug. According to the marks, it was made in Porto sometime after 1938. I would appreciate your help on the maker. Thanks in advance

[Funkel]

Hola:
Hello:

Se trata de Riobom y Cª, L.de . Registrada en Porto en 1945 y cancelada en 1953.
This is Riobom and Cª, L.de . Registered in Porto in 1945 and canceled in 1953.

Mira la marca de este lado y verás una R al lado izquierdo
Look at the mark on this side and you will see an R on the left side

[svc]

Muchas gracias Funkel. I really appreciate your help