If you want the 4-channel model, you can get ten of them for $4.80 shipped from AliExpress.
You can probably get away with a smaller cap on the output if you want to make it a bit smaller. I use a 10uf tantalum cap on the Super-Chuffer for the filtering, it works just fine. Of course, I was going for size, so I wanted the smallest cap that would do the job at 60hz. Also, the smoke power and TMCC headlight is coming in half-wave format, so I'd need much more capacitance than you would with full-wave power.
