$resp = $ua->get($url,
  'Accept' => 'text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5',
  'Accept-Language' => 'ru-ru,ru;q=0.8,en-us;q=0.5,en;q=0.3',
  'Accept-Encoding'        => 'gzip,deflate',
  'Accept-Charset'         => 'windows-1251,utf-8;q=0.7,*;q=0.7',
  'Connection'             => 'keep-alive',
  'Keep-Alive'             => '300',
  'Cookie'                 => 'id=12345'
);