Thanks to everyone for their input, I checked the suggested sites
The Hanger 9 cowl has been discontinued they only have one for smaller plane, I looked on the Carbon Copy site and they do have 2 cowlings that would be suitable, Thunder Tiger Cub cowling which is similar and has the dummy engines on both sides the other is for the Great Planes J3 cub which is a bit bigger at the firewall but could perhaps be cut down, but has no dummy engines, I looked on the Great Planes site and found a list of online retailers and on the Tower hobbies site I found a J3 Cub cowl with 2 dummy engines and 2 Baffles so I think I will give them a try.
Thanks again to everyone.
Les