With the proper tools, I would think that a fiberglass blank would be easy to work with. But the blank would need to be near finished deminsions and one would need a CNC machine or be better with hand tools than me.
I think the best bet would be to have Bullberry alter a Factory synthetic stock to fit your 2-hole hanger bar. Just tell them you have this size..... ie .800" or whatever you have.....barrel and need a 2 hole forend. They will inlet it for the hanger bar you have. They bed a piece of wood in the forend and then inlet the wood....my bro-in-law has one.
Then it will look like a factory synthetic...but we can get around that. You would need to fill the checkering with bondo....glass bedding compound etc. And you could also add width or shape with the compound also. After it cures, sand to shape.....rough it up with 100grit sandpaper then clean it with degreaser. Then I can explain the covering and painting process.
If you would like, have Bullberry make it and I can do the rest. I would get a factory forend and practice first. Let me know...I love this kind of project!!!
Otherwise, try to find a used wooden VVGC forend for the 2 hole hanger and it can be covered to match.
If you need any help, email me or post.
Kyle
topboss8@yahoo.com