Those numbers don't cross with any Perkins parts that I could find. *I usually shop heat exchangers and oil coolers from The Manifold Warehouse. *They seem to have a very good selection for Perkins applications. From their home page, click perkins, then click product list and scrole down to manifolds and coolers.
http://www.manifoldwarehouse.com/mes/mgr?brch=home
*
Good luck
Larry B