Fresh water tank screwcap

[Bulldog Winnie]

I have recently purchased a pilote exploratory g741. When I tried to remove the screw cap to pull the plug on the fresh water tank, it looked like it had been tightened with a hammer. When I eventually got it off, it didn't look like it was the proper cap. The thread on the cap didn't look like the thread on the tank. Does anyone know where to purchase a new cap.

 

[Figaro]

You could try Cak Tanks

 

[Jev88]

Measure outer and inner dimensions of neck of tank and take photos. Cak tanks are usually great.