Can antimony pentafluoride be made by adding hydrogen fluoride to antimony trifluoride?
It can be prepared using hydrogen fluoride, in a double displacement reaction:


  $\ce{SbCl5 + 5 HF -&gt; SbF5 + 5 HCl}$


However, hydrogen holds onto fluorine more tightly than does antimony in $\ce{SbF5}$. 

Consider the reverse of your proposed reaction, which is preferred energetically:


  $\ce{SbF5 + H2 -&gt; SbF3 + 2HF}$