I bow to the greater expierience of others  but it looks like a combined English Crown & broad arrow army property stamp to me. 
 
I cant recall an upside down arrow before though.   Thats very strange to my eye. 
 
ill have a look through my references over the next few days though. 
 
Skennertons is worth a shot. 
 
Spiral
		 
		
		
		
		
		
		
		
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