Here is a Meccano Invoice from January 1959 for a Hornby Dublo Goods van, a Dinky trade pack of No 168 Singer Gazelles and a trade pack of No. 178 Plymouth Plazas.
The Singer and the Plymouth were both introduced as new items in January 1959.

A Google search reveals that C Cunningtons were a shop dealing with radio, television & electrical supplies & repairs, Meccano, hobbies and cycle accessories in the 1950s. They were located in the High Street at Wheathampstead, Herts.
A nice little piece of Meccano historical documentation.
Dave
An other great find David.
Dave
You must have acquired this little gem through eBay! A previous post "Dinky Toy Sales, Ordering, Promotions, Retailing etc" my comments referred to the same dealer in Wheathampstead, as I bought a small quantity of Invoices, Advice Notes etc from his son, Alan, through eBay!
Small world!
Bruce
.
Dave
You must have acquired this little gem through eBay! A previous post "Dinky Toy Sales, Ordering, Promotions, Retailing etc" my comments referred to the same dealer in Wheathampstead, as I bought a small quantity of Invoices, Advice Notes etc from his son, Alan, through eBay!
Small world!
Bruce
.
Dave
Here are a couple more of the Advice Notes covering sample Dinky Toys.
Kind regards
Bruce 
All three are addressed to Cunningtons. They will have come from the same e-bay source.
I have some more paperwork I will put it on later.
Dave
Yes, Dave, most likely as I wrote a few days ago. Following on with the Advice Note, came the final invoice as shown below.
Yes, also from the same source, thanks Alan Cunnington for putting them on eBay!

-561 and 961 Blaw Knox Bulldozer (1946-64)
Membership renewal
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-Boxes General Discussions including end flaps, both British and French
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-537 Renault 16 TL
-Boxes General Discussions including end flaps, both British and French
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616-AEC with Chieftain Tank
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-073 Land Rover, Horse Box and Horse (1960-67)
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-073 Land Rover, Horse Box and Horse (1960-67)
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-105c and 383 4-Wheel Hand Truck (1949-1958)
-105c and 383 4-Wheel Hand Truck (1949-1958)
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