[gobs]

It might be worth checking out

this one,
they sell bits and bobs to make your own.

[muntjac]

you can get the blue water pipe from builders supplies and its dam cheaper than ready bought coldframe ones . cut to size  

[flatcap]

if you see any builders ,modernising warehouses buildings etc ,have

a look in there skip for blue water pipe ,thats were ours came from ,builders were quite happy to get rid of it