Just keep in mind that the reason you found them in Kilspindie and Madderty is because the death records survive in those parishes for those times (look back at the link I gave you above). So that does not mean that there weren't other Margarets and Mungos dying in the more likely parishes, just that the records don't survive. However, no harm taking a look while you're in Edinburgh, since it won't cost you any more

Madderty is closer to Crieff and with some luck the record will mention her husband (with a great deal of luck, actually

)
Regards,
Sarah