Lada Niva is essentially ancient car from 1977 which changed very little since then. It's awesome cheap car with extreme offroad capabilities, -1 star safety and poor reliability. Interesting and unique combination of properties in modern world.
There's also Lada Niva Travel which was developed in 1998 with a bit different market orientation.
Lada Vesta is most modern Lada development and it's not directly based on Renault tech. Lada Granta is a bit older Lada which is in-house development as well. Those are not 4x4, though.
I have no idea whether those cars are sold in Europe. Probably not.
For the sake of £10k I'd take a 5* safety rated car, likely with a better finish and quality overall, over a 3*, and as much as I'd like to be understanding about budgets, there's plenty of reliable, high-quality, safe cars on the used market for much less than their new-price.
Is there any _good_ reason to buy a mediocre car new for £20k, over a £40k+ car with a few years on it for £20k? I'm asking genuinely because I don't know, I'd buy the used car every time.
EDIT: Typos
But don't forget to put the children in child seats appropiate for their age. Else the 5* will become 0*.
Many of Dacia's newer models get 1/5, some 2/5, and only the Sandero gets 4/5, their highest score (in this market).
In the UK, a Duster starts at £20k for the base model , while something equivalent with a 5 star rating like a Nissan Qashqai or Kia Sportage starts at £30k.