I made bymyself the springs of the 7x17 (copper).
The springs for the 11x14 come from a on old back 6.5x 8.5 Rittreck camera.
I don't sell the camera but I use them with great sadisfaction.Unfortunatley I have to buy the film from USA since there is not 11x14 B/W format negative at this moment here in Japan.
The springs have the same size and shape of a Kodak 2D camera (just cutted them).
Easy job.