Possibly a bit late now, but I tend to buy MOD surplus MVP (moisture vapour permeable - similar to Goretex) waterproofs.
If you go for RAF, then you get blue rather than army cammo patterns - though the heavy duty army ones are harder wearing (typically reinforced knees) and bigger zipped leg openings for ease of putting on over boots, so better for working in if you don't mind looking a bit like a Walt.
Typically available sub £20 on ebay in unissued condition, you just need to figure out the NATO sizing (waist, bum, leg). There's very little can touch the quality for the price, and they are cheap enough to be disposable if you do manage to rip them. I wouldn't use them in preference to a modern high-end goretex (they aren't as nice to wear or as well designed as cycling specific stuff, for example), but do great for working outside, walking the dog, using as an extra layer on the motorbike etc.