Private lessons-Science Teacher Required for Two UK schoolboys

I'm looking for a Retired or working Science teacher living in Thailand to Privately Tutor my two sons aged 10 and 13. The boys have been in Full time education in the UK since they were 5 and recently arrived here. We live in the North East. I am retired and i am home schooling them, quite successfully. However Science is not my forte. 
The job would suit ideally a retired person with lots of free time in the day and pay is open to negotiation. We can travel most anywhere for tutoring , even Bangkok, and stay over in order to make a longer trip worthwhile. The boys are energetic, sporting and catch on quick. They don't speak any Thai. Mom is a Director of a Thai Government School  and we both feel Thai Schools would serve them no purpose. International schools in our part of the country ( Buriram ) don't exist and moving to Bangkok full time is not an option given the nature of my wiles job. So Look forward to hearing from you if you feel you can help