No, you don't have to spend more money on a table saw. And no, there is no such thing as a rip fence for a scroll saw.
What you will have to do is practice, cut slowly, practice, guide the line into the blade, practice, take your time, practice.
You can sand the edges down for a smoother edge by taping a piece of sand paper to a flat surface (bench, table or a piece of glass or Formica or something). But of course you might want to cut the pieces a sliver larger to allow for the sanding loss.
Rog