Toy Aster Cash Register Age

I have come across this Aster tin toy cash register and am amazed by its quality and am intrigued to its age. I have found a couple of posts on the internet of the same item but am a little confused to the details in their description and true value.

This aster register is in excellent condition and in full working order. Other than a couple of scratches as seen in the photos, the only thing wrong with it is the 10 and 20c buttons are missing.

In regards to the age, one post I found stated that it was a 1950's production but the decimal currency was only introduced into Australia in 1966 so a little unsure as to why they would have 1c 5c and also $1 on the buttons etc. I do however also have some cardboard cutout money prints of the 1,2,5,10,20 & (round) 50c piece so can only assume that this play money was made pre 1969.

The register as shown says
Aster
Cash Register
Pat No.
465054
465315

and just above the register draw is a symbol of a tree with OKP in the middle and 'Made in Japan' underneath the tree.

I am curious to see if this is a collectable item and if possible the value of it as this is a quality toy and even if collectable but not worth alot then I will let me children experience a toy of such quality unlike those of today.