I have a Gunlocke chair similar to the one pictured (not mine). Most of the original foam in the seat has gone to powder. There was a big stain and I think someone destroyed it trying to remove the stain or maybe whatever caused the stain destroyed it.
Anyway, what density / firmness foam do I need to ask for. The original foam was like firm foam rubber. From what I've measured the foam would have been about 1-1/2" thick. All I have to reference the original foam is this not-very-good picture of the foam as it went into the trash, it was pretty disgusting to handle, orange powder everywhere.
Oh, and I've not seen this type of foam at the local fabric store so I may need to mail order. Any recommendations for US suppliers?
TIA, 
The original foam was
latex, which you can still get. Try foamsource.com. They do custom cushions and they sell various densities. Firm or extra firm would be best for a seat.
You can determine the original thickness by measuring the fabric at the side. The foam will have compressed so it's not a good indicator of thickness now.
You can also use a good quality polyfoam.
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