They changed at around that time >

The box on the left is a box I know 100% belongs to a 1967 WG1803 It is 53.00.01

The box on the right was the newer one I believe it was replaced with. This one is 71.00.55 (I bought this one loose so cannot be exactly 100% sure)

I know that with some models came in different boxes for different markets so 71.00.01 sounds like it could well be very well correct if you combine these two numbers I have together.

You really need someone who has one from that year with it's original B+P to be exactly sure.

Do you have a picture - that would be a big help rather than trying to play with numbers.

Steve