Pages overlapping problem

Have you tried using a cutoff shader? Should remove the z-fighting, here's a simple one that doesn't cull the back of your pages.

 Shader "JM/VertexColoCutoff" 
 {
 
 //Jona Marklund 28th August 2013
 
     Properties 
     {
         _MainTex ("Base (RGB)", 2D) = "w$$anonymous$$te" {}
         _Cutoff ("Alpha cutoff", Range(0, 1)) = 0.8
     }
         
     SubShader 
     {
         Pass 
         {
             Cull Off //Could be set to Back 
             AlphaTest Greater [_Cutoff]
 
             CGPROGRAM
             #pragma vertex vert
             #pragma fragment frag
 
             uniform sampler2D _MainTex;
             uniform fixed _Cutoff;
 
             struct appdata 
             {
                 half4 position : POSITION;
                 fixed4 texcoord : TEXCOORD;
             };
 
             struct v2f 
             {
                 half4 position : POSITION;
                 fixed4 texcoord : TEXCOORD0;
             };
 
             
 
             v2f vert( appdata IN )
             {
                 v2f OUT;
 
                 OUT.position = mul(UNITY_MATRIX_MVP, IN.position);
                 OUT.texcoord = IN.texcoord;
 
                 return OUT;
             }
 
             
             fixed4 frag(v2f IN) : COLOR
             { 
             fixed4 colorOut = tex2D(_MainTex, float2(IN.texcoord));
             
             return colorOut;
             }
             ENDCG
         }
     }
 }

Hope that works. Best Regards Jona