I don't know how much appearance you need to change/can change on a DS to make it look more like an off-roader. In full disclosure my other vehicle is a Jeep Cherokee I've had for 18 years, and it has a few simple mods like a 50mm lift, underbody armor, and a 2" hitch receiver (gives a strong rear recovery point -- my DS has one too) and it's always done well off-road.
You ought to subscribe to the UK DS forum at
https://www.discosportforums.co.uk/ There is a lot of off-road discussion there, especially from the Ozzies who seem to spend a lot of time off road.
No one makes a bullbar or winch bumper for the DS.
Underbody armor (AKA skid plates or bash plates): do a search for Rival skid plates. Supposedly they don't impact your ground clearance.
Lift kits: there's a lot of discussion on both this forum and the UK one. Short story is that DSs (and any vehicle with independent suspension) are difficult/expensive to lift. Check out this thread:
https://www.discoverysport.net/forum/tires-wheels-suspension/12544-lift-kit-disco-sport.html
Hopefully you have 17" or 18" wheels. A tall, flexible sidewall is part of your suspension system, absorbing shocks before they reach the rest of the components. I would have gotten 15" wheels, like are on my XJ, if I could have, but 18" is the smallest offered currently. I believe a 17" wheel may have been offered in pas years. Putting 20" wheels on a Land Rover is just nuts.
Speaking of tires, your DS probably arrived like mine (a month ago) with all season highway-biased tires. I don't know why Land Rover wouldn't put AT tires on a Land Rover, but they did. I have Firestone Destination AT on the XJ and they're great in snow and off the pavement. They don't fit the DS, though, but there are AT tires that do. I'll be watching the wear on these Pielli Scorpion Verde All Seasons.
Anyway, here is some info to check out and chew on. Please keep us posted as to where you go with this little project.