Hey Ron, the ???mit is one word, I can not think of a word that fits yes, it looks like senmit of fenmit or henmit, but those are not words,
You go pretty close with the translation
Dear Richard
A small joy for you, it goes completely well for me, A heartty greetinig from you father inthe field, Joseph
I suspect that you are aware that K.u.K. stands for Kaiser und Konig, the title of Kaiser Karl of Austria-Hungary at the time of the writing of the card.
Best
Gus