Where to purchase acer laptop charger??? Backing plz ?

Hiaa
My Acer laptop battery charger has broke, well the adapter part, basically there is a slit/ chop in the wire and its either not method halogen all, or smelling of burning once its pluged in and if you move the wire, dark blue sparks are upcoming out of the wire etc, true yes... pretty much buggered lol. the plug itself is ok, its righteous the varied end, adapter part.
Would any regional pc repair shops or pc shops sell any replacement chargers for cheap? or do anyone know a good website where they sell good chargers for cheap? Im from the UK so ,Uk based site. I looked on ebay and saw ones for about £5 / £6 but scared wont work.
Any help please?
Thanks x