capacitive sense touch keying circuit for Morse code transmitters

I am the owner of RadioSet-GO, a source of innovative, portable, QRP (low power) HAM radio equipment. I used to purchase capacitive touch key boards to integrate with my projects and they worked perfectly. Unfortunately, the owner of that business passed away, and I am left trying to come up with something just as good. I have attempted several circuits myself with only some success. I have a lot of insight into the subject that will help. Here is what I need: A capacitive sense touch keying circuit for Morse code transmitters. It needs to be small (I will make it surface-mount), operate on 12VDC, be energy efficient, and self calibrating. It will have only two inputs , one for dits and another for dahs. The input contacts are metal endcaps which mount to the outside of Pelican boxes. Touching the contacts with finger tips will switch the iambic keyer inside the radio and cause it to transmit. Touching both at once and holding will result in both switches closing and an alternating di-dah-di-dah-di-dah sequence by the internal keyer. Switching resistance must not exceed a certain value, and needs to be stable. It needs to respond to touch as instantly as possible, without false readings or 'self-keying'. It also needs to be immune to RFI and not generate noise in the receiver. The circuit will be used in a variety of RF environments with different antennas, up to 15 watts PEP. Those are the general requirements. The circuit that worked so well for me implemented two 12F683 IC's. I have included a circuit diagram, so if you can create a .hex file to make this exact circuit work for me, that would be ideal. If you feel you are suited for this project, I will provide more helpful insight. Thank you!