Seeking observation time in secondary school

Hello,

I will commence a teaching position in the UK later this year. I am required to undertake five days of observation in a secondary school prior to the commencement of this position.

However, as I was offered this position as recently as April 11, this has left me in a tricky position, as terms are ending quite soon, as I understand it. Not to the mention the fact that

(a) I work full-time, 9am-6pm Monday Friday [Though getting time off work would probably not be a problem]

(b) The recruiters would prefer I did my observations in England/Wales [The flights at short notice, accommodation, transport etc does make this a little difficult].

Can anyone recommend the best way of contacting schools, finding lists of schools and so on? If not in England, then even in Dublin, as I live here and it'd be much less hassle than flying abroad and seeking out a place to spend the week.

Thank you