fumigated
high-density foam from clark rubber ~$50
'hot' knife from from bunnings ~$40
fumes from the 'shaping' activity - priceless
seriously do it your self
even make your self a cover for it
(or get Nana to knit you one)
- othewise some (thieving) sod is bound to quote you 5 figures for a 'customiser-seat-aviation-one-of'
my 2 cents