Recently we pulled the planter out of the back of the tractor shed which hasn't been used in probably 40 years.  This planter is the kind where the hoppers and mechanisms mount to the cultivators frames on the left side of the tractor and the layoff plow and planter foot attaches between the cultivator frames underneath the tractor.  We did find all the pieces but the flat link drive chain is pretty rusted, stretched, and generally worn out.  I'm not sure how to measure this to tell you what pitch the chain is.  The best I can do is tell you that the opening where the tooth of the sprocket rolls into is about 3/4" lengthwise.  Does anyone know where I can find this chain, it really needs replacing?  We are having problems getting the main drive from the sprocket on the rear wheels to the planter to stay on.   Trying to get this ready for the spring planting.  We are going to leave the mule planter in the shed this year and plant our sorghum, for making molasses, with the Allis B.