These large crowns are made of copper-nickel and do not carry much value. In fully uncirculated condition they may retail for $5 US dollars or so. Nice coin, nevertheless.
An interested reader named Tim submits this for your consideration:
The 1965 Churchill coin came in 2 versions like the Charles and Diana coin. There were 9 million of the normal coin struck and they are pretty worthless. However, the VIP version has a rainbow type shine in the metal compared to the dull normal coin. There were only 1000 VIP coins struck, and the last time I heard they were said to be worth £1000 each.