It's really sad that you are having to go through this.
I would suggest you get some advise from some professionals on what direction to take.
I would guess that ordering a complete turn key engine would be a better way than trying to deal with your present engine.Shipping it to the USA or attempting to rebuild it ,with the needed machining,in Greece doesn't seem to me to be the right direction.
Here are two known professionals I would contact and discuss all your wants and options with :
Brent Lykins (502) 759-1431
brent@b2motorsportsllc.com
B2 Motorsports, LLC Products
Keith Craft (807) 246-7460
Keith Craft Performance Engines