This GB cinderella overprinted "5/- 5/- MALTA" was sold on
ebay yesterday:

seller:
chibs3link:
http://www.ebay.com/itm/380470587954price: £25.86 + £8 P&P
I have never seen this cinderella in auctions or on the internet.
Do you think that the overprint was produced in 1937? Or is it a modern fantasy overprint?
I am asking because after searching several times on Google, I found absolutely no reference to any overprints by the colonies on British 1937 cinderellas, except for those issued for the Canada and USA royal visits in 1939. Moreover the font looks suspicious.
If this was really issued in 1937, I think there would be
some reference to it somewhere.
The other possibility is that it was done in 1937, but by an individual who made them for him/herself and did not sell them.
What do you think?