As above really my 4x4 rear calipers r becoming old and tired, the hand brake has started to fail, so its time fora freshen up,

wheres the best place to buy the service kits and any advice while im doing the over hall

 

Try Big Red. They do service kit, seal kits and much more, including complete calipers. Good service and nice prices

 

just spotted the on ebay, they look good, any advice when fittin?

 

They are good. To give you an example, the piston for a front caliper brand new CNC-machined from billet metal cost me £9 delivered.