I just realized; a 40 tooth rear sprocket makes the overall ratio in 6th within 1% of the stock 5th ratio, so it will be like riding around in 5th gear, so why change? However, a 38 tooth rear almost exactly splits the difference between stock 5th and 6th ratios. I'd be interested in a 38T sprocket, but have changed my mind on a 40.
Regardless, I have a used stock rear sprocket that Sprocket Specialists could use as a pattern. Puchman66, if you want it to send to SS, I'll send it to you, or if you do place an order, I probably could send it directly to SS (assuming they agree they can coordinate my sprocket and your order).