how to increase selection criteria??

how to increase selection criteria??

I have this statement:

    $(function() {
        $('em:contains("$0.00")').each(function() {
            $(this).html("Call for Shipping");
        });
    });

It's not specific enough, it won't work if it's $20.00 for example...

How can I put a wildcard to catch characters between the $ and 0??

OR

This is the way it gets rendered on the html if it's not $0.00

<em class="ProductPrice">$20.00</em>

Otherwise if it's $0.00 jQ changes it to

<em class="ProductPrice">Call for Shipping</em>

and before THAT the website renders this radio button (from the server-side code):

<label>
<input type="radio" name="selectedShippingMethod" value="0" style="vertical-align: bottom;">
"Call for Shipping"
</label>

I need to have ONLY the $0.00 or any dollar amount associated with this specific radio button or label changed to 'Call for Shipping', IF the label value is 'Call for Shipping' how can I do this??

Is it possible to only change the em value following this specific radio button?? If so, how??

Basically I must do:

<air code>
If <label> contains 'Call for Shipping'
and
<em> contains $*.*
then
replace $*.* with phrase 'Call for Shipping'
end if

Here is my jsfiddle: http://jsfiddle.net/STbk8/10/ or http://jsfiddle.net/STbk8/13/

jsHint is not helpful with the parens and brackets!! :( which I know are not correct but at least I have this in some sort of JS/jQ format for people to look at...

Actually I do not need to check for the <em> value but the em value is what must change.

I'm more a frontend html/css person, not a jQ/JS ninja :(

My current little one-liner will affect anything with $0.00 and I can't use a portion of $0.00 or that will mess up other things...

Thank you, Tom