Block Mode Study & Part-Time Work

Im about to commence a masters course which is full-time but in block mode. I haven't yet been given the timetable but its something like 1 week in, then between 2-5 weeks off. In total i think im in for about 9 full weeks.

I will need a job during this time but i dont really know what the best type of work is for my timetable.

I cant see a new employer being happy with giving me a week off every 3-6 weeks (it would be different if i had an established job already but i dont).

I also dont want anything too heavy because i had quite a tough job during my undergraduate degree which almost affected my ability to get work done.

Does anybody have any experience with block mode study like this, and can you possibly make any suggestions for jobs? Also am i best waiting till i start uni to get a job?