After fiddling around with blue silica gel crystals to put in my three plastic equipment container boxes, I decided to buy a proper moisture absorbent product, and use all my existing silica gel for a CCD air dryer pump I am presently making.
This crowd have been mentioned on IIS before, and are well worth a look:
www.silicagel.com.au, located on the Gold Coast. I bought 4 of their 40 gram packs for 9.95 each, with free postage. I bought them on Ebay Sunday night, and they were here in outer Brisbane Tuesday morning. Each in a sealed plastic package, so you can keep a couple spare and ready if you want.
A nice convenient metal pack about Iphone size, that you can throw into any plastic container, and the indicator looks like it's actually using some of the crystals, so it shouldn't lie. The aluminium case looks like it could be opened, if you wanted to change crystals for any reason, and the whole shebang goes straight into an oven for reactivation, (but being metal, not in a microwave).
So for under $40, I got 4, and they suit my astro needs down to a T.
No affiliation with the crowd, just putting in a good word for the product after buying some.