basic bridge body is easy. Where things get exciting is spreader bars and bug net. Spreaders are a solved problem using tent poles from questoutfitters, relatively inexpensive and easy to integrate into a bridge hammock.
Bugnet....well I'll tell you, if the idea is to get something together quickly and surely you might consider making a "wrap-around" bugnet. Just a matter of using enough netting...think a really long tube going past the suspension triangles, with channels at the ends, with drawcord so that they can be cinched closed. Maybe even sewn closed at the end except for a hole for the suspension line to get through. A zipper in the middle to get you in and out. A car camping solution to be sure, but you're car camping, right?
No, not sil. Used to be sold by Sportsman Guide, but they haven't been offering them now for over a year.Forgot to ask if your camo tarp is silnylon.