Hi,
There's no better way to get attention than to threaten to scrap something uncommon, rare and unique!
Don't do anything hasty there. My bed and sides are pretty rusty but I would never think of scrapping them just because I'm missing a few parts. I do have a front headboard and front troop side. I can make a very accurate dimensioned drawing from the original so that a metal fabrication shop could make one for you. It's not a complex piece.
The only thing I may ask in trade is for you to provide me with some detailed photos or dimensions of parts and assemblies of your M756A2 that I'm missing.
Let me know and I'll pull it from the pile this afternoon and start sketching...