Hi folks, late in here.
Sorry but imho it is not Monart. The lack of pontil is clear, but also the technique is just different to that used by the Ysart's.
Colours are Schuster & Wilhelmy/Kügler and widely used even today so do not really any help with ID.
I have seen this before, smaller pieces, but never managed an ID. It is possibly that it was made by Strathearn, Deacons or Chic Young. But Deacons used a pontil rod, not a gadget. Strathearn is most likely if it is Scottish, but not sure if they used Kügler colours.