Just road use. (I'll have the original set of wheels which have Deestones on them which could potentially be used for any non-road but no plans for that.) It's mostly just pottering about locally but I have taken it on holiday which is usually 90 miles away so reduced engine speed (and noise) on longer journeys would be useful! I recognise there's a trade off with acceleration.
Size wise you have a bit of choice. A 205/80R16 would have sort of been a standard fitment back in the day. Not quite this size, but it is pretty close. They will work fine, but are on the smaller side and will perhaps leave it wanting a little visually.
A 7.50 x 16 is also a standard size and is a fair bit taller while remaining narrow. This will improve the looks, off road performance and allow slightly better cruising speeds. There isn't a huge amount of choice in this size though, although some good options.
Next up is a 235/85R16, this is about the same height as the 7.50 just a little fatter and is a standard Defender size. These can work too and give more choice than the 7.50 although IMO the 7.50 is a better size, esp on a Series.
Anything wider and you'd probably need to consider different rims. Wider tyres are also likely to make the steering heavier too.
I would avoid going for anything period looking tread wise. Most of the old looking tyres are completely rubbish on or off road. Mud Terrains will look the business, but tbh if you don't plan to off road a more road biased tyre or All Terrain might be a better bet. But does depend on what size you go for.
BFG offer the KM3 Mud Terrain in 7.50 size. It is an extremely good tyre all round, so still suitable for road use. But they are a bit pricey.
If you mostly plan on road use, something like this will probably ride and drive well:
All terrain FT-7 is designed to conquer a range of terrains As used by Palmer Sport on their off road course, tackling a multitude of obstacles and...
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