P200 Engines

I want to fit a P200 engine to my VBA but since the cost of a new engine is so high I have been looking for second hand ones.

But I am confused:-

Can someone tell me the differences between P200, PX200, PX200 EFL …

I want an engine with oil mixing (auto-lube?) and electric start. Can a non-electric start be converted by adding an electric start casing? What about the auto-lube?

Thank you.