With asp.net-mvc, can I include stringified json into the query string or a url?

I have the following code that i am using to run a controller action on my asp.net-mvc site:

asp.net-mvc Controller Action:

public ActionResult MyAction(PostParams myParams)
{
   //go do stuff
}

where PostParams is defined as:

public class PostParams
{
     public int Age {get;set;}
     public string Name {get;set;}
}

Javascript Code:

$("#myButton").live('click', function (e) {
    window.location.href = "/MyController/MyAction?Age=10&Name=Joe";
});

NOTE: Before someone responds with "You should be using Ajax", I am unable to use ajax here because my controller action is returning a file as per this question here.

I now need to pass in some additional data which is the result of a jquery UI sortable list like this which comes in as json. so that looks like this:

$("#myButton").live('click', function (e) {

    var sortables = $(".sortableList");

    var arr = [];
    sortables.each(function () {

    var statusParam = new Object();
    statusParam.Ids = $(this).sortable("toArray");
    arr.push(statusParam);
});

    var myResult = JSON.stringify({ result: arr });

    window.location.href = "/MyController/MyAction?Age=10&Name=Joe";
});

My question is, what is the correct way to include the "myResult" into the query string where it will show up on the server side correctly. I have tried this:

    var myResult = JSON.stringify({ result: arr });

    window.location.href = "/MyController/MyAction?" + myResult + "&Age=10&Name=Joe";
});

and included a new field in the PostParams like this:

 public class PostParams
 {
     public List<MyItem> result {get;set;}
     public int Age {get;set;}
     public string Name {get;set;}
 }

 public class MyItem
 {
     public List<int> Ids { get; set; }
 }

but result always seems to be null when I check it on the server side.