Jack,
Welcome to the group.
I will try to address all your questions as best I can:
*It will probably be some five years before the trees start producing something;
*As John said Mission is a cultivar from California, and Lucca is a toscanian oil cultivar from the Lucca province;
*I do not believe you can adapt the fruit press, for olive oil extraction one needs very high pressures (400 Atm);
*The same thing applies for the grain mill, the olive nut is really hard and you will probably end up destroying it;
*| suggest you try one of the small scale solution from TEM (
http://www.tem.it/) or from Pieralisi (
http://www.pieralisi.com/) , I'm sure their sold in the US;
*The olive tree is hardier them oranges and figs, so you will probably will be ok;
Hope I've of been of some assistance.
Cheers,
Joćo
Cascais - Portugal