what application for this?

[Bob Phillips]

I have a couple of these NOS carbs but in spite of a long internet search, cannot determine the application. Can anyone help? It is a sidedraft Solex 35RZPAIPO or maybe 35RZFAIPO. Is about the same size as an M151 carb.
The only ebay listing I could find says WW2 Bedfor- but that seems unlikely.
Can any of our UK members help with this??
solex1.jpg

solex2.jpg

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