Just wanted to say I luv the Rover 2's. Mine is bare of any seating and the paint is mostly gone but it still cuts the grass perfectly. I am looking for another one and e bay cops a pounding in my search. Don't know if this is of any use but my original 70's engine is long gone and the following is installed, working fine.
B&S I/C model 193702, type 0131 01, code 87073009.
Good luck in your search