I looked at Importing a Single Symbol From a Different Font and Handwritten R-like-kay. As a result, I downloaded the STIX package and looked up the highly welcome curly k \kay and found it to have the "coordinates" stix-mathscr (on page 37 of the newest documentation v1.1.1-latex from 2014/07/3); they are:
15x, ''6x '3
What does this signify and how can I use it to import it? I guess the actual code would be similar to the answer in Importing a Single Symbol From a Different Font. Sorry, if the question is a bit redundant, but I think for non-experts the whole symbol importing business is pretty hard to understand.

ms andns, I would probably prefer\usefont... ;). – cfr Nov 10 '14 at 23:35t know to which extent follow up questions should be posted here, but I wonder how to make this\kay"less italic" so that it fits better with the\ell` of Computer Modern, which I wanted to use in the document. It should work similar to the fake italic. – w_w Nov 16 '14 at 23:58\DeclareFontEncoding{LS1}{}{}
\DeclareFontSubstitution{LS1}{stix}{m}{n}
\DeclareSymbolFont{stixsymbols}{LS1}{stixscr}{m}{n}
\SetSymbolFont{stixsymbols}{bold}{LS1}{stixscr}{b}{n}
\DeclareMathSymbol{\kkk}{\mathalpha}{stixsymbols}{"6B}
\DeclareMathSymbol{\jjj}{\mathalpha}{stixsymbols}{"6A}
\begin{document}
The $\kkk$ is more slanted than $k$, the $\jjj$ more than $j$ and so on. $\kkk\ell$ are different, too. \end{document}` – w_w Nov 17 '14 at 11:24