Yes, definately throw that bike away!...
The majority of Sears J.C. Higgins Balloon line was produced for them by Murray. There are many exceptions to this rule though and especially in the period between 1946 and 1950, several suppliers were used to meet the immediate postwar demand for new bicycles. While Murray produced the lion’s share of the bicycles examples from that time period have turned up that were made by Monark, Westfield, and Shelby but none of those variants appear in the standard Sears Consumer Catalog.
An interesting side note is that the earliest postwar Sears’ bikes that were likely available in 1945 and early 1946 were still badged as Elgins before the J.C. Higgins name was applied to the Sears Bicycle line. Both Murray and Westfield postwar Elgins are known to exist in the hobby today.
Also, on frame dates, I find the process of decoding serial numbers and divining the actual production dates for bicycles to be more fun than actually riding them. Peculiar perhaps, but I guess everyone needs a hobby….Since I have the knowledge I generally share it when an impossible or unlikely date for a bike is posted. This is not to make anyone wrong but for mainly two reasons; the primary reason is in case the owner would like the additional information about their bike, and secondly; many people reference the posts and photos on this site to date their own bicycles. If they are searching for photographic references and production date information, the added information will be useful to them.