After 18 months of searching I've found a replacement for the Kempax K504/5 pump made by Raritan
The valves on mine had lost
their flexibility and I couldn't find any to match and the exposed cover was brittle and ugly.
I found it after seeing a catalogue shot that looked similar. An email
to SPX Sweden
resulted in an email
from the Customer Service
Manager in Illinois that gave me the new model number of the old Kempax.
The Canadian distributor had no stock and I didn't want to wait 10-12 weeks so I found 1 in stock at Pump Vendor. They shipped quickly and now I have a Johnson 70-50005 Viking pump.
The only differences are longer inlet/outlet tubes for better clamping and black coloured plastic parts
. Replacement parts
are also available.