Sorry to hear of your medical limitation. Regrettably there is NO method of receiving remuneration on a JAR/FCL PPL for Flight Instruction.
There is NO NPPL yet, NO agreed process for future NPPL holders to add ANY ratings to their licence, NO agreement for NPPL-holding FIs (if, that is, they are allowed in the future) to receive any remuneration for SEP work......
You might, however, wish to speak to the BMAA about requirements for remunerated microlight instruction?