The Collaborative International Dictionary of English v.0.48:

Unfeigning \Unfeigning\
   See feigning.

Moby Thesaurus II by Grady Ward, 1.0:

89 Moby Thesaurus words for "unfeigning":
   arcadian, authentic, bona fide, bucolic, candid, card-carrying,
   dinkum, direct, following the letter, genuine, good, guileless,
   homespun, honest, honest-to-God, inartificial, lawful, legitimate,
   lifelike, literal, native, natural, naturalistic, naturelike,
   original, pastoral, pure, real, realistic, rightful, rural,
   simon-pure, simple, sincere, sterling, straightforward,
   sure-enough, true to life, true to nature, true to reality,
   unadorned, unadulterated, unaffected, unartificial, unassumed,
   unassuming, unbeguileful, unbeguiling, uncalculating, uncolored,
   unconcocted, uncopied, uncounterfeited, undeceitful, undeceiving,
   undeceptive, undesigning, undisguised, undisguising, undissembling,
   undissimulated, undissimulating, undistorted, unembellished,
   unexaggerated, unfabricated, unfanciful, unfeigned, unfictitious,
   unflattering, unimagined, unimitated, uninvented, unpretended,
   unpretending, unpretentious, unqualified, unromantic, unsimulated,
   unspecious, unspoiled, unsynthetic, untrimmed, unvarnished, verbal,
   verbatim, veridical, verisimilar, word-for-word