Looking for mastering

We are a band from Málaga (Spain) that self-produce our music. But as a final touch, we want to master our songs with an engineer who has mastered some of our influences. We would like to know what is the price per song and if we could have one song ready before the end of the year and the rest of the EP (3 more songs) for the first week of February. The songs would be for online distribution only, it is not necessary to prepare for vinyl.