I think the DZ47 series is made by Yueqing Henghao Electric Co., Ltd [China] they are made in many formats B type and D type single, double and three pole. An internet search shows many suppliers for example Electrical Components Direct but never used these myself.
As to 16A MCB's the rest of Europe has 16A supplying radials as they don't use ring main system and in this country most off peak heaters, immersion heaters, ovens etc would use this size.
Read answer to your other post. Suggest you consider hard before going down DIY route.
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