Homebrew PCBs

I use a Panasonic KX-P6500 laser printer for making prototype boards
with Dyna Art paper, which seems to work fairly well for me. However I
am thinking of trying to make some silk screens for small volume PCBs
and I think I need to be able to print a "positive" of my PCB pattern
onto transparency in order to make the silk screen.

By positive, I mean that the copper tracks will appear white when
printed on paper, and etched portions will be black. My PCB software
does the usual "negative" print - copper tracks are black, etched
areas white, but not the positive print.

I use Ivex Winboard for my PCBs, and to do this would require another
Ivex product costing $199.00.

However there may be drivers or other ways to do this, can anyone advise?

Grant