ok im going to have to accept that the bottom end has gone

so i found a guy who says that the ford fiest rs turbo h reg, is the exact same engine as the ford escort g reg (mine) and is willing to sell me the bottom end for £150, or the whole engine for £200. is he talking out his ass? or is it something i should go through with.

ethe engine is out of the car, so how can i see iff the bottom end / engoine is fine. ?