the minila DOES NOT use standard keys. it has a completely unique layout to every other keyboard. just fyi.
sure it uses mx keycaps, but the width of the keys is also important, as well as the combination of legend and specific width.
for example, the bottom left ctrl is a 1.75x key, whereas every other board uses 1.5x or 1.25x.
your best bet is to buy dsa blanks.
there are 4 factors to determine if a key can be 'replaced' by another key: legend, width, row profile, and concave/convex.
blanks means that legends are not a factor. dsa keys all have the same row profile. dsa keys come in all widths. the remaining problem are the 3 convex keys on the bottom row - there are no equivalents in DSA keysets.