I figured this would get buried too quick in the general board.

I mounted a PSOP on my rifle and It does not fit so well in the case any more.  I figure I can replace the 1.5" egg crate with 3 0.5" layers and do cutouts.  

Where can I find this type of foam?  Might it be readily available locally?  And is there anything special about it?  

Thanks.

You can get egg crate foam at Hobby Lobby or other craft-type stores.

Otherwise check with the manufacturer of the case.  Normally they sell replacement foam.

All the foam I've found in hobby stores was white or green. I couldnt find anything in black or grey.
On option though is acoustic foam. Its used in sturios and high end homes to controlling reflections. Theres a home audio store by where I live that I checked at and they had some scraps they gave me, after talking to the guy for a minute he asked what it was for. I told him and ended up he was a Makarov collector so we hit it off real well. Chatted for a bit and he gave me there scraps from a previous job he had done.
Anyways, long story short if you cant find a grey or black in hobby stores check a home audio store and ask for acoustic foam.
Heres a pic of the foam. It is a bit rougher then normal foam, its not all Charmin soft and squishy. Shoudl work perfectly for your needs, it gives good support for the weapon and looks good as well.

http://fox302.com/index.pl?s=vf&user=Shockwave&category=Guns&file=Case_open.jpg

Forgot to add!! You can also find it online if you cant find it local.
Partsexpress.com -> search "acoustic foam"

http://www.partsexpress.com/webpage.cfm?&DID=7&WebPage_ID=3

I'll have to check those out.

Any more ideas?