Early A ('65) Bucket Seat Foam: Make Your Own?

Is there any reason one can't do it oneself? Is the foam offered for sale reinforced with metal framing or something like that? I have two '65 Abodies and would need four of these and don't have time to wait for another inheritance. Thank you.

Edit: I previously introduced this post saying: "These a now selling for $380.00 each. I can purchase a mountain of foam for that price." But I could not find that "deal" when I looked for it again later. Must be a mistake. Please see post #4 for more reasonable prices.

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