Love inuendo....it is best when the audience laughs....and the heckler is clue-less.
JIBES are so impromptue - and dependent upon the IMMEDIATE (fractional seonds) that I cannot recall "gag-lines" that will work.
There is a spontanity and rapoire' you must work out with each, individual audience....(but for some strange reason...different people in the same venue seem to draw the same responces.)
If you are not naturally "vulgar, rude, crude, lewd" (and most I,IV,V er's are not) you will need several weeks immersion in the "bawdy threads" area of the DT to develope the talent.
A well "strapped Barbor's Razor slash" above the gonads .... can leave the hapless heckler wondering why there are two red marbles on the bar-room floor."