Ordered silicone cast form, bought a crockpot (worked 10x better than i hoped it would for melting) and starting casting my own wax bases. Pretty satisfied with them. Yes, I know they are not rectangular ....but i did not want the form to overflow or the sheets become too thick. I need to cut them a bit anyway and Like all beekeeper mistakes : the bees will fix it.
I considered rolling but wondered if it would not stick to the roller easily. Then again, it's not uncommon. This just seemed easier and more affordable. Buying Form + cooker was less than €60:-