I have a Mission Olive tree, and I've read in several places that Sevillano and Ascolano will both increase fruit set as these 3 are good cross pollinators of each other. Unfortunately I cannot find any Sevillano or Ascolano in my area, all that seems to be available locally is Arbequina, Frantoio, Manzanillo, which from what I've read are either poor cross pollinators or not compatible at all.
My question is would buying a 2nd Mission Olive increase pollination rates? Is it just a matter of a greater amount of compatible pollen available in the area or is there something about the genetics of cross compatible varieties pollinating each other that gives better results than just having multiple trees of the same type?
(I know I could order a Sevillano or Ascolano online but I've been very disappointed in my previous mail orders, most arriving near death or disappointingly smaller than advertised, so I'm focusing on local trees I can inspect and approve of prior to purchase)