Give Joe a call or e-mail at Proctor. Keep in mind, he's a 1 man shop and so he can't jump every time the phone rings and he tends to answer e-mails later in the day.
He'll sell you a set of plans and a construction manual for a reasonable price. Then you'll have them on hand. Also any individual parts you may need, ribs etc you can get individually. Ask him for a catalog too. Helps with all the little bits.
(503) 668-8612
[email protected]