As I said on the vectric site, easy enough with a good photo, I've recently done a front window for an airport bus from 6mm acrylic because they couldn't get hold of a glass panel for several weeks.
Both front windows were same so used the one that wasn't broken, masking taped round the edge to give me good contrast, took photo, imported photo into software, drew round the edge to give my shape (don't generally use an auto trace) & plotted the shape to a large bit of paper. Cut out the shape & compared to original window, was a bit out in one or to places so noted where & made alterations to nodes. Plotted & cut out again but was still a little out on one edge so repeated the procedure & third template was spot on.
Your panels aren't fitted to the vehicle so you could draw on new stock with pen as Jazz has said.