In London and brought my car from OZ

[Bean]

the original fascias are two pieces, though I doubt you'll find someone selling you just the mph bit. Your best chance is to find someone in UK or Ireland to sell you one of their clusters and put it in.

Not entirely sure on UK law but I though the fly off type is legal as long as you can secure it in the pulled status. Braided line should be fine I guess.

Someone from the UK will be better to answer that.

You'll need at least a temporary fog light at the back to pass the MOT.