Just Bento

Eden foods (Clearspring in the UK) get their Mikawa Mirin from this Japanese manufacturer
http://www.mikawamirin.com/index_e.html

It's well regarded with a long history, so it's a mystery to me why their Mirin is available through this overseas distrubutor with no alcohol in it.
(Especially as this Q&A about non-alcoholic Mirin features on their website
スーパーで見かけるみりんは、よく見るとみんな「みりん風調味料」と書いてあります。みりんと違うのですか？
本物のみりんはアルコール分の入ったお酒の一種として酒税の対象商品です。しかしスーパーではお酒の販売許可を持っていないところもあって、そういう店が置く「みりん風調味料」は、醸造工程を経ず、化学製品や人工甘味料などの合成でできたアルコール分が入っていないにせもののみりんです。本物のみりんの旨味を味わいたい方は、お酒を扱っているお店で買いましょう。)

Anyway, I'm currently using Kikkoman mirin, and that's hardly the best, it's got corn syrup and the tiny amount of alcohol was probably added, so I doubt it's in any way superior to the Eden foods Mikawa Mirin.

Have you checked out the label on Takara Mirin? I saw mentions on the net of their organic mirin being the sort you're after, but could only find the regular takara mirin online.