I had to run it in for a few weeks, but she go's like a horse on crack now
But it would be easier and cheaper to get a new motor if you can't do the labour your self.
You should only need to skim the head if it's warped, and there shouldn't be any need for a p&p.
All up it took about a week to rebuild my redtop. By we did all the work and we work at a garage do getting the block honed was free. All so got a nice little discount on parts
If your going to rebuild it though, replace every thing you can. eg. water pump, leads and the dizzy and any thing else that is on it's way out