An interesting glass decanter from Japan

I have no idea who made this, so if you have any ideas, great!, speak up!

I acquired it with a consignment of glass from Japan, and it really has a very Japanese style to it, and I now believe it is Japanese made.

It is a lovely orange and has inclusions of a gold glass with black threading. It has been mould blown and I think the squashed sides have been done afterward.

Strangely the base has moulded numbers (I can't read well) and over the top of the base there has been a layer of glass added to cover the moulding.
It feels like a sheet of toffee when I tap it but I'm a bit wary of prying it off.
No evidence of a stopper, it is 18cm tall.

What do you reckon all???