I checked
Pohl.
Still no match. But
Pohl notes that Huszar 881 (which is as close to your coin as one is going to get; minor
legend variation) was struck in 1527 with the mark K-T with the Jagiellon
eagle. Louis II Jagiellon died in 1526 so a few stray coins with
his symbol in the next year makes sense. But your coin was issued three years later from an unrelated
mint. I offer no explanation. Enjoy the coin!
By the way, if you are unwilling to tackle the
German, there is a new book on
medieval Hungarian coinage in English (although it ends with Matthias Corvinus and would not include the Jagiellons or Zapolyai) that you may like as a supplement to Huszar and
Unger. It was written by Jedrzej George
Frynas and is available through
Spink. It offers less information than either of the books you have, and does little to update those books, so I suggest it only for the use of English.
Stkp