Is it the case these letters are similar in writing in either Burmese or Sinhala scripts?
I checked the Sinhala and Burmese and to my untrained eyes K and T looked alike!
ක vs ත
က vs တ
P.S.: I produced the above by rendering Ka and Ta from IAST into the aforementioned scripts using the cool tool the topic below is about (thanks @virtualvinodh!) :