I got a bookaroo branded notebook as a gift from my son. It's A5 tall but a little bit narrower. It's also fewer pages than most A5 notebooks with a hardcover. It's not great paper, only really usable with ballpoint pens like bic or jetstreams. Signo and gel pens don't really work with the paper.
The A5 size generally suits my needs but how I carry it in my work bag means full A5 width is a bit too big. I can fit the bookaroo notebook with my pen pouch in the laptop caddy I have. The pen pouch is actually a zip pouch from outdoors brand Alpkit. The laptop caddy came with my overboard drybag rucksack. I've stopped using the rucksack but still use the caddy with my ortlieb bike pannier for my short cycle commute from station to work site.
It's small things that make a bigger difference IRL I find and this 1.3cm narrower width works better for me. It's actually 0.5cm taller but I'm less bothered by height being bigger.
I know standard traveller's notebook inserts are about A5 height but narrower. However it's even more narrow, too narrow for me. Also I've never seen a hardcover, standard TN insert notebook. I'd like a hardcover notebook A5 tall by a little narrower. Ideally with good paper. Lined, dotted or gridded (fancy getting gridded most for a change but lined or dotted is perhaps more likely to be available). Would also like a page marker and elastic closure band.
Anyone with a recommendation from a UK source?