I know it may be not the right forum for this, but still hope to reach people interested in such exchange.
If you have an unmodified NTSC motherboard from a 65XE or 800XL machine and would like to exchange it for a PAL motherboard, I'm interested.
Another possibility would be to exchange the complete computers.
We could first share photos to avoid misunderstandings regarding the items condition.
I live in Europe (Germany) and the shipping costs accross the ocean may be siginificant (sending a motherboard only may be cheaper than sending a whole computer). I haven't checked it yet.