Hygrothermograph chart stock

I am having trouble locating a supplier of replacement charts for my
Weathertronics hygrothermagraph model #5020-A.  The charts are
numbered 50202 with the number ecn. no. 2563 at the bottom.  Any
information will be appreciated.

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                  Conservation DistList Instance 9:73
                    Distributed: Sunday, May 5, 1996
                        Message Id: cdl-9-73-015
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