i think (but dont know for sure)the near side rear inner cv is knackered only place found to replace it is about £85, i have found out that grade a do a second hand drive shaft for £40 + vat and delivery
but have just spent £100 on prop because i thought the problem lie there (it doesn't)
I have a vibration under acceleration and going up hills when the car warms up, the near side rear inner cv boot had come off at some point and i had driven through france into spain and back again, and flung grease every where so i am now assuming that the cv is knackered due to lack of grease.