I have a single arm chair that needs recovering and repair.

The nylon webbing under the centre of the seat has worn through and created some secondary damage to the foam directly above. I have removed the fabric under the chair to see the extent of the problem.
The attached photos show the chair and the underside. Please let me know a rough estimate of repair ( I understand that this might change as you view the chair personally) and recovering might cost (I can source and supply the fabric).

I appreciate your time and reply.