Something

<SCRIPT language="JavaScript1.2">
function product_sku_search_popup(mylink, textbox_id)
 {
	if (! window.focus)return true;
	
	var href;
	var keyword;
	
	keyword = document.getElementById(textbox_id).value;

	if (typeof(mylink) == 'string')
	   href= mylink + "&textbox_id=" + textbox_id + "&keyword=" + keyword;
	else
	   href= mylink.href;
	
	window.open(href, 'sku_search_window', 'width=660,height=400,scrollbars=yes,toolbar=yes');
	return false;
 
}
</SCRIPT>

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<form name="product_sku_1557" action="https://www.premiere-supplies.com/admin/?" method=GET>
			<input type=hidden name=page value="rma/rma_process">
			<input type=hidden name=func value="updateRMAItemProduct">
			<input type=hidden name=rma_id value="3749">
			<input type=hidden name="rma_item_id" value="1557">
			<table width=100% cellpadding=0 cellspacing=0 border=0 class=BasketTable>
			<TR class=BasketTableRecord>
			<TD nowrap width="20%"><b>
			<input type="text" id="product_sku_1557" name="product_sku" value="" size="10" maxlength="64">
			&nbsp;&nbsp;
			<input type="image" name="save" value="Save" SRC="https://www.premiere-supplies.com/templates/premieresupplies/images/b_complete.gif" border=0 width=20 height=20>&nbsp;&nbsp;
			<A href="#" OnClick="return product_sku_search_popup('https://www.premiere-supplies.com/admin/?page=rma/rma_browse_skus/print&', 'product_sku_1557');" alt="Browse">
			<img src="https://www.premiere-supplies.com/templates/premieresupplies/images/b_browse.gif" alt="Browse">
			</a>
			</b></TD>
			<TD width="75%">Brothern TN-350&nbsp;&nbsp;</TD>
                        </TR>
			</table>
			</form>

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IN THE POPUP
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<SCRIPT language="JavaScript1.2">
function product_sku_return_value(textbox_id, product_sku)
 {

	window.opener.document.getElementById(textbox_id).value = product_sku;
	window.close();
	return true;
}
</SCRIPT>
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<a href="#" OnClick="return product_sku_return_value('product_sku_1558', 'EXT-TN350'); " alt="Select This Product">
	   <img src="https://www.premiere-supplies.com/templates/premieresupplies/images/b_edit.gif" alt="Select this product">
	   </a>