Does anywhere stock cheap cordial/squash in Japan in 2022?

I’ve found some old threads that make the situation seem dire, but my largest unexpected bill in Japan has come from the lack of squash so I’m wondering if any products have surfaced in the last few years!

For anyone who doesn’t know as I think it’s British term, Squash is basically about a litre of condensed juice. You add water to some and have a drink. It’s about 300/400円 and can do you for about 20 cups.

I’ve been buying the big bottles at supermarkets of various drinks but still go through them very quickly compared, so if anyone knows anywhere that stocks these that’d be much appreciated!