If there’s a “British Store” nearby they’ll probably have it. Along with Flake bars and crazy flavoured chips. Mmmm, roasted chicken crisps. Plus they’re sure to have Will and Kate plates, cups, flags, tea towels . . .
Sometimes British import stores are masquerading as other things… one Canadian town I lived in had a British sweet shop. I only found out after years of walking past it that it carried loads of British products, like Marmite and canned Spotted Dick and all sorts of weird, wonderful, giggle-inducing things.
If you’re not indoctrinated into one or the other, I suspect you will. I just had Vegemite for the first time a few months ago after years and years of Marmite, and I might just say that I prefer it to Marmite. I think they’re both wonderful, yeasty spreads, although Vegemite is a little less sweet and a little easier to deal with (it’s not as thick and syrupy as Marmite. It’s more like a thick peanut butter in texture.)
You definitely need some fat to go along with it. A big schmear is fine if you’re used to it (I use pretty thick amounts myself), but it doesn’t taste right without some butter or other fat to complement it.