If (as suggested) there is any way you can pull up the floorboards then I would personally cut the pipes back until they were under the floor.
I would chase out the plaster to just under the sink. Then embed polyplumb plastic pipe into the wall under the floorboards and reconnect.
Messy - yes - but by chasing out the wall behind you get a great finish
I hate exposed pipes with a vengence!
If your sink has a half pedestal then it will hide the entry points for the pipes
Much nicer not to see any pipework.!
If your sink is exposed you can drill neat holes into the tiles and bring through chrome pipes from the wall
