Re: drill your own sprocket?
I've used regular one piece sprockets. The hole for the crank lines up perfectly with the 9 hole pattern on the rag joint. As far as drilling the holes where you need them shouldn't be a problem.
This is the sprocket I use.
BMX Accessories - Solid Chrome 36T Sprocket, bike sprocket, bicycle sprocket, bike chain ring | BikeWorldUSA | Bicycle Parts and Bike Accessories
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