Jon, you might to take a look at the FET circuit Radiofun uses after the ceramic filter in this video. He specs either a BF245 or a BF256.
The video is 17mins 35 seconds long, the key bits are close to the end, but it's all worth watching, jumping forward occasionally!.
https://www.youtube.com/watch?v=mTqXWB6RSOA
B