I think maybe it's fel-pro at Napa.
Do not remember the part number.
Has metal re-inforcement imbedded inside.
Use tin snips to cut.
The sheet at one time came as about 16x16 but now 12x12
Napa might have to order.
I seem to think I seen it at O'Reillys but not sure.
I've even used it as intake...