First and foremost, your select values are ambiguous. They contain values that can filter AND sort the entries - Separate the two since they are two different functionality.
Next, you need to define a custom Filter which will filter the data based on the rating selected. For this, you enhance the filtering criteria with the "Rating" property to associate the rating selected with a rating value.
Finally, associate the sorting with a predicate and a reverse value - the predicate determines the property / column to determine for the sort (price in your case) while the reverse determines the ascending / descending nature of the sort.
The entire code can be found here - http://plnkr.co/edit/n7TebC?p=preview
I have updated the plunkr and introduced comments so let me know if you do not understand a code.
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