It’s probably an illusion that Hornchurch was named after these horns, but it seems there was a bull’s head and horns on an earlier church.
But the Resurrection Window appears to be post-medieval:
Note computer, Spitfire and car:
Details of how to ring and ringers’ jugs at The Bells of Hornchurch.
I was impressed that they were ringing this lunchtime, but was told that it is all about Waterloo, and too jingoistic for my informant.