2 of 2 added 127 characters in body

Python 2, 38 bytes

Though input is only required to support a-z, this should work with any single-line input that doesn't contain NUL bytes.

s='s=%r;print s%%s#'+input();print s%s

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For input abc the resulting quine is:

s='s=%r;print s%%s#abc';print s%s#abc

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