Ok, so two new developments.  I have decided to scrap the idea of using monks cloth as it is just way too costly.  And so linen it will be and I will just add pleats to give it texture.  Secondly I have decided on a new look for my wife's costume:

and then mine will remain like this:

So as soon as I am able to afford the fabric and can locate someone to help me make it then I shall begin.  I have no sewing skills at all, and even less skills cutting and piecing together a pattern.  Wish me luck.