Advice On Best but But cheap Breastpump

When i had my first i found it hard to feed her as i got really sore but the pump i had was not very good, this time i want my baby to have my milk and though i will try my best to do it naturally i would like a pump just in-case i don't manage it as with my first i pushed passed the pain but ended up getting mastitis and a abscess scare which made me very ill for some weeks and by time i was better my milk had stopped.

Any advice on Electric pumps would be great as it was 6 years ago i got my last one and no idea what i am looking for