Halfrauds have Vibe slick Sub and amps for 150quid
I would personally say get 6x9's but most would argue that 6x9's and subs don't work well together.
http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_50 4839_langId_-1_categoryId_165702
But It does depend on how much "expensive" is.
