Sukhothai ware ... really?

The previous owner of these said they are old sauce bowls, which were passed on to her from within her family.

According to her, these bowls were owned by an ancestor who was a labourer building the Saigon Railways - which began in 1881.

She did not know where or when her ancestor obtained them.

I have only been able to find the following information regarding the fish motif from the Southeast Asian Ceramic Society:

"This example represents one of the most renowned types of Sukhothai wares: the underglaze black fish motif. Although there are no clear sources of inspiration for the earliest depictions of fish and flowers drawn in black (Miksic 2009: 63), such decorated wares can be found in abundance at several different sites in Southeast Asia, for example at the Tak Om Koi burial site along the Thai-Burma border.15th C" (photo to follow in this thread ...)

Whilst I do not believe the age of these goes back that far, I am interested to know anything about them - especially their age. Could these possibly be 'Sukhothai ware'?

Height 3cm/1.25" Diameter 4cm/1.5"

Quote from Wiki about Sukothai ware,
'Ceramics based on these styles are still made at present and widely exported, particularly to the Philippines and Indonesia. '
So really, without cast iron provenance, it historical relevance is completely unknow,

Thank you both for the responses. I am still in touch with the previous owner ... she has said she will find out more information regarding the bowls ... dates and places, so I will wait on her and give feedback as soon as I get it. I have to say that I am inclined to see these as modern (ie 20th century), but she was telling me something different ... hopefully she will get some provenance that will wow us all!