Help with microdata rich snippets

Hi,
I am trying to implement rich snippets into the individual product pages of my website. I have checked it over and over again and it all seems to be correct but the Google testing tool reports:
"Error: In order to generate a preview with rich snippets, either price or review or availability needs to be present."

One of the pages that I am trying to get to work is:
http://www.metalsignsdirect.com.au/tin-signs-7537/HD-Nice-Catch-Babe/

And the snippet of the code that I am trying to work is:

<div class="pdetails" itemscope itemtype="http://data-vocabulary.org/Product">
    <img itemprop="image" src="/GetImage.aspx?id=7537" alt="Metal Signs, Tin Signs, Antique Signs, Old Signs, Vintage Signs, Collectable Signs, Decorative Signs" />
    <h1><span itemprop="name">HD Nice Catch Babe </span></h1>
    <p class="indcat">
    Category: <a href="/863/Motorcycle-Signs/">Motorcycle Signs</a> &gt;  <a href="/1177/Harley-Davidson-Tin-Signs/"><span itemprop="category">Harley-Davidson Tin Signs </span></a></p>
    <p class="ppdesc"><span itemprop="description">Harley-Davidson authorized embossed metal sign measures 15" height by 13" wide</span><br />
    <span class="dim"><b>Dimensions:</b> 38.1cm x 33.02cm</span><br />
    <span class="dim"><b>Model Number:</b>  <span itemprop="model">2010811-63B</span></span>
    </p>
    <p itemprop="offers" itemscope itemtype="http://schema.org/Offer" class="dprice">AU $<span itemprop="price">24.75</span> each
    <link itemprop="itemCondition" href="http://schema.org/NewCondition" />
    <meta itemprop="currency" content="AUD" />

    </p>
   
    <p style="text-align:right;">Qty: <input name="ctl04$TextBox1" type="text" value="1" id="ctl04_TextBox1" class="txtQty" style="width:18px;" /><input type="image" name="ctl04$ImageButton1" id="ctl04_ImageButton1" src="/images/addtocart.png" align="absmiddle" style="border-width:0px;" /></p>
   
</div>

HTML:

Is there something that I am missing here? It all seems to be correct to me, but I am still getting this error.

Thanks,
Cameron Johnson