I made the large bunker a few years ago, & will probably make a couple more smaller ones. I'm considering alternate Barricades & IED options for my PLO force, who (like the Japanese in the original Crossfire rules) will get 2 Bunkers, 2 Wire, & 1 Minefield in their standard package.
I made the bases by joining two of the 50x25mm pill bases together (I am counting my smaller Ø25 bases as the 'standard base size' for rules purposes, meaning that these strips fit the rules definition of 4x1 bases area). The 'razor wire' coils are florist wire from a craft shop, twisted around a pencil, & painted gunmetal silver. The Wire posts are sections of cocktail stick; whilst I used sections of matchsticks for the Minefield markers. The bases are textured using paint thickener & sand, & decorated with a few tiny bits of Gale Force 9 flock & static grass.