My day job is with a lighting and staging company, we help 1902 out with their pit every year, the last couple using a small truss arch in the front and some simple stands in the back...here is the only picture I have from this year:
http://imgur.com/WuL0pjW
If you are serious about purchasing a truss pit send me a message, we are dealers for many truss lines and might get you a more realistic price. I think for a 10x10 it was around $1500 (before freight) last time I priced a cube design out, but I could be completely wrong.