What I've read leads me to believe solar stills do produce condensed water, but I've no idea whether it would be in sufficient quantities for a cp collection.

And this is weird: Apparently the water might not be 100% pure. If you put a container of dyed water in the still to evaporate, the water that condenses will have a visible amount of dye in it. At least that's what I saw in an online video when I looked into this.

Do you get any condensate runoff from your air conditioner? That might be worth a try if you can collect it.

Another option might be a reverse osmosis system.

I know just how you feel! Buying distilled water is just too expensive especially if you are raising more and more plants that need it. You need a good R/O system. It makes life easy. I made the change. What you need:
A rain barrel, the r/o system, and a watering can dedicated to r/o use only.
If you have the money to burn then you can add pumps and special hosing that you can pump your r/o water out of the rain barrel to water your plants.
Check the links found at the Goggle page below-I have no idea what you will find but check as many as possible to get the best deal and learn about the systems.

Here is a link that might be useful: goggle links to AU R/O retailers

Most car washes use RO water for the spot free rinse. That's where I get the majority of mine when I run out of rain water. Just ask the owner or attendant. I'm sure they would let you fill your jugs for little or even no cash. Make sure to get some TDS PPM test strips and use them every time you get water so that you know the water is good before you fill your jugs. The water I get tests at 15 PPM but anything less than 100 should work.

Thanks for the advice! I might hit my local carwash first and see how that goes... and look into an RO unit in the meantime

Ta
Bunks