If there aren't any companies that would custom
build them do you know of a website or resource that would have information on how to
build them and suggested materials? I don't know the first thing about how to construct them or how they would be safely installed.
Any scene shop will be able to
build you a set of portals, bring them out, and install them. If you give a
call to whoever you buy your
theatre supplies from locally, they should be able to
point you to a good shop in your area. If you are going to be taking these things down and putting them back up often, I would suggest going with steel, preferably .049 MT1010 with rigging points attached.
Just a quick google search:
San Diego Opera Scenic Studio
One quick note and taking off the TD hat and putting on the LD hat. Talk to your LD before you go through the investment of curved portals. They are nearly impossible to light a
stage around. They look great, but they
block about 70% of your upstage/
downstage shots off your electrics which makes for rather
flat lighting. The only way to get around this is to do numerous tail downs on an
electric. Its a real pain and can really affect how the final product looks. Have whatever shop you have
build the
portal build it so that the curve is removable allowing you to have a standard square
portal and a curved
portal.