It depends on how good of a rig you want. You can get a bike off bikesdirect.com for $250 at the cheapest and it will get you around town for sure. Or if you want something a little better, you might be looking at something around $450-$550. If you custom build and go all out, well thats anywhere from $700-$2000.
there really is no goo answer to your question until we find out what exactly you are in business for.
Traitor cycles makes one (25.4mm) Unsecure image, only https images allowed: http://www.traitorcycles.com/images/Hooligan_1.jpgSpank SPIKE 777 EVO (31.8mm) they make a couple different rise options Unsecure image, only https images allowed: http://www.spank-ind.com/upload/20090828_095113833104.jpg thoes are just two i could think of off the top of my head. i think all city, orgin 8 and a couple other of the 'fixie' companies make some polished riser bars but if i remember right most are 25.4mm
or go down to your LBS, have they look for a cheap pair of chromoly handlebars, i know SBS and QBP have a few and they cost like $15. be warned tho they tend to be boat anchors.