Worked electronic distributor

I have a stock 308 and Im looking for a electronic distributor. I have found a second hand one for sale but it was come off a worked 308. The owner has told me that it has been remapped to suit his engine/cam. It has had the time advanced to 34 degrees.

My question is - when looking for a 2nd hand electronic distributor should I stay away from dizzies that have been on worked motors if mine is stock?

When it comes to iginition I am stumped.........

Timing is set when it is installed in the car so that doesn't matter, but if it has been regraphed then no you cannt use it, not without having it remapped again, I personally would buy new if I could afford it, it was always one of those items that seem to give niggly trouble when worn and second had, but maybe thats me