I did not know of a website where you can see it. However, I put the complete historical spreadsheet file up on the Data Files page of my website www.bwts.com.au at the end of every month. It is quite easy to download this and chart it in Excel. However, you do not need to chart it. There is only one calculation point each month and what you need to know is easily seen from the last column of the spreadsheet without plotting it in a chart.
Subsequently a member has found a website and let me know:
I stumbled upon a charting website that has the Coppock Indicator available free.
Coppock is available by clicking the chart icon (the one in-between the cog and the scales). See my example attached.