I copied this info from the Poche family website.
http://pochefamily.org/outboard/
Hope it helps. Not sure if price is still current.
David
FOR SALE JOHNSON LEATHER PRIMER PUMP SEALS for TD, TN, etc.
If your old Johnson drips fuel from the carburetor when you push the primer, you need these seals and instructions. If you have tried rubber O-rings or other materials, you already know they won’t work. Gaskets and cork floats are easy to make, but these leather seals are very difficult to reproduce so that they work properly. Don’t worry. These are new seals made from pump leather, as original, and fit all old 5 hp, 4.2 hp, and 2.5 hp Johnsons including Models TD,TN,AT,LT,DT,HD,HA,HS, etc. Includes detailed diagrams and instructions for proper installation that are not found in the Factory Service Manuals. The instructions alone are indispensable. Not necessary to remove carburetor.
Send $8.00 per set (cash only, no checks) and SASE (self addressed stamped envelope) to: Lloyd Lautner, 9289 North Long Lake Road, Traverse City, Michigan 49685
Stop leaking and keep yourself and the "tree huggers" happy!
Lloyd Lautner AOMCI