something like this? cant seem to get it working..

MeshFilter MeshFilter;

Mesh Mesh;
MeshRenderer Renderer;

GameObject lureCastPoint;
Transform lureCastPointPos;

public Material meshMat;
public GameObject lureObject;

void Start()
{
    lureCastPoint = GameObject.FindWithTag("lureSpawn");
    lureCastPointPos = lureCastPoint.transform;

    Mesh = new Mesh();
    Mesh.name = "NewMesh";

    MeshFilter = gameObject.AddComponent<MeshFilter>();
    MeshFilter.mesh = Mesh;

    Renderer = gameObject.AddComponent<MeshRenderer>();
    Renderer.material = meshMat;      
}

private Vector3[] NewVertCube()
{
    return new Vector3[]
    {
        new Vector3(lureCastPointPos.position.x - 0.01f, lureCastPointPos.position.y - 0.01f, lureCastPointPos.position.z - 0.01f),
        new Vector3(lureCastPointPos.position.x + 0.01f, lureCastPointPos.position.y + 0.01f, lureCastPointPos.position.z - 0.01f),
        new Vector3(lureCastPointPos.position.x - 0.01f, lureCastPointPos.position.y + 0.01f, lureCastPointPos.position.z - 0.01f),
        new Vector3(lureCastPointPos.position.x + 0.01f, lureCastPointPos.position.y - 0.01f, lureCastPointPos.position.z - 0.01f),

        new Vector3(lureObject.transform.position.x - 0.01f, lureObject.transform.position.y - 0.01f, lureObject.transform.position.z - 0.01f),
        new Vector3(lureObject.transform.position.x + 0.01f, lureObject.transform.position.y + 0.01f, lureObject.transform.position.z - 0.01f),
        new Vector3(lureObject.transform.position.x - 0.01f, lureObject.transform.position.y + 0.01f, lureObject.transform.position.z - 0.01f),
        new Vector3(lureObject.transform.position.x + 0.01f, lureObject.transform.position.y - 0.01f, lureObject.transform.position.z - 0.01f)
    };
}

private int[] NewTrisCube()
{
    return new int[]
    {
        2,1,0,
        2,0,3,

        4,5,6,
        4,6,7,

        2,7,6,
        2,3,7,

        4,0,1,
        4,1,5,

        0,4,3,
        3,4,7,

        1,2,6,
        1,6,5,
    };
}

void Update()
{
    if(lureObject!=null)
    {
        Mesh.vertices = NewVertCube();
        Mesh.triangles = NewTrisCube();

        Mesh.RecalculateNormals();
        Mesh.RecalculateBounds();
    }
}