Where to find stem ginger in London

Where can I find jarred stem ginger in London? I’ve looked in Waitrose, Tesco, and Sainsbury (in Edinburgh) and Asda and M & S in York. No one even seems to know what I mean, but I’ve seen it called for in a ginger curd recipe.
I’ll be in London for the next few days. Any suggestions where to look?

Sorry if this ends up in the wrong place. First time using HO on mobile and it isn’t going well.

It should be in the baking sections of most supermarkets - it maybe called known as ginger.

Here it is on some of the supermarket shopping site:

http://www.waitrose.com/shop/ProductView-10317-10001-13996-Waitrose+Chinese+stem+ginger+in+syrup

http://www.tesco.com/groceries/product/details/?id=264908041

http://www.sainsburys.co.uk/webapp/wcs/stores/servlet/gb/groceries/sainsburys-stem-ginger-350g?langId=44&storeId=10151&krypto=FsZwNWH9rEW9vNAVybRNGJcB6jxYp3GNzg0WYXTy%2BbJU2xrlcQ4%2FiReAZPFDtFEyHPFbAdj0M4sfDYy19n6pB4rgR9l3HPOg66ula12EMzSN04az8dFDk9E8XK0KxO83E2Pm3ZqQ2a4CxxYtSp4IOyxZWsg8d6xAb2eL%2BNKRX%2B4%3D&ddkey=http%3Agb%2Fgroceries%2Fsainsburys-stem-ginger-350g

Success at Waitrose on Edgeware Rd. I have no idea why I couldn’t find it elsewhere.

Is there anything else you’d recommend I buy that I can actually get into the States (so no black pudding or haggis - yes, I like them both)?

I would suggest getting some Old English Hunt marmalade from Fortnum and Masons. It’s my favourite marmalade, nicely bitter which perks you up of a morning.

“Food is a pretty good prism through which to view humanity.”

― Jonathan Gold