So, Chris set about fixing it, with my beloved pallets. He even made a gate with a latch and a self closer. Yay Chris. <3
He made this with
2.5 pallets broken down and all nails removed
1 length (3m) of 90mm wooden fence posts cut to 1m lengths
6 masonry bolt things
3 U shaped brackets to hold the posts up
6 massive bolts to fasten the U brackets to the timber
Lots of galvanised screws for outdoor use
1 latch mechanism
Some chicken wire (for the gate so they could see out a bit better)
and an automatic closer (which was given to us)
The entire job cost about $30.
If you're drilling into concrete use a masonry drill bit and a rotary drill (not a hammer drill like some recommend).