Stihl 038 Ignition Upgrade?

[Stihl_Ben_UK]

I have a very good mid 80's (at a guess) Stihl 038 however its no longer producing a spark.

 

Photos below of the original ignition system. I see lots of different topics and threads about these, I understand I can order alternative aftermarket parts to replace the original ignition trigger and coil assembly but could anyone provide a link to the parts I would need. 

 

Thanks in advance!