If you want to use silica gel just buy bulk, or buy multiple units on sale. My last purchase for silica gel was $94.05 for 2.5kg of indicating gel, $69.35/2.5kg for non-indicating gel (work use). I mix some indicating in with the non, when my blue stuff goes white I dry the whole batch. I routinely add 10-20% water weight into my gel before drying it, I dry it before it's saturated.
If one doesn't work you can buy 5, the system is scalable.
For drying I regularly use a casserole dish in the oven or microwave. It's fine to microwave (in a microwave safe container), 500 grams should be done in 5 minutes, that's what the indicating gel is for though to tell you when its done. It smells a little weird, like drying sand, that's normal.
Be careful if the gel gets dusty, the dust is bad for the lungs, it's very important to read the MSDS on this one for handling instructions. when you constantly mix/pour it gives off dust, the rest of the time it's harmless.