SELECT a.n_izd, a.town izdTown, a.n_post, s.town postTown, countK
FROM (SELECT j.n_izd, j.town, (SELECT spj.n_post
                          FROM spj
                          JOIN (SELECT n_post, sum(kolvo) countK
                                FROM spj
                                WHERE n_izd = j.n_izd
                                GROUP BY n_post) b ON spj.n_post = b.n_post
                          JOIN s ON spj.n_post = s.n_post
                          WHERE spj.n_izd = j.n_izd
                          ORDER BY s.reiting DESC, b.countK DESC, s.name
                          LIMIT 1) n_post
      FROM j) a
JOIN s ON a.n_post = s.n_post
join (SELECT n_post, n_izd, sum(kolvo) countK
      FROM spj
      GROUP BY n_post,n_izd) x ON x.n_post = a.n_post
WHERE a.town= s.town AND x.n_izd = a.n_izd