Driving down the m69 today and the gear shift spat out of fifth and almost broke my hand!!!!!

The deafening crunches were shortly replaced with absolute silence...
Anyway, I heard it is possible to take a 2.0 8v bottom end and mate it to a 1.8 8v cyl head.
or what is the simplist complete 2.0 8v motor I fit straight into mine?
I need to sort it ASAP so ANY help you can give would be much appreciated.
Cheers. Mark.