If you want Burlington Arcade in a Dulux tin, go for Dulux Jewelled Creek 2. It lands at a ΔE of 1.9 from the original Mylands colour, which is well inside the "very close" bracket (under 2.5). With an LRV of 21.5 it holds onto that deep, inky teal-green character that makes Burlington Arcade No.216 such a cracking colour for a study, dining room or a moody hallway.
The runner-up is Dulux Teal Voyage, sitting at a ΔE of 3 with an LRV of 20. That's a touch further off — you'd likely clock the difference if you held them side by side — but on a wall, on its own, it'll still read as the same family. If Jewelled Creek 2 isn't easy to get hold of, Teal Voyage is a perfectly respectable fallback.
Now the honest bit: a colour match across brands is never the whole story. Mylands paint has a particular depth and chalkiness to its finish that Dulux won't replicate exactly, even if the hex values line up. Mylands' Marble Matt Emulsion has more pigment and a softer, flatter look than Dulux's standard matt. So if you're matching for the *colour* — patching, budget, or just preferring the Dulux supply chain — Jewelled Creek 2 will do you proud. If you're chasing the *feel* of Burlington Arcade, nothing but Mylands will give you that.
One practical tip with deep teals like this: always get a sample pot and paint two coats onto a bit of lining paper, then move it round the room across the day. These colours shift dramatically — they go almost black in low light and reveal their green in daylight. North-facing rooms will pull them colder and bluer, which can be gorgeous or gloomy depending on what you're after.
Whatever you land on, prime properly over any patchy or previously coloured walls so the depth comes up even.