We have a Stripper rope cutter on our 120S-E saildrive (3 blade prop, so 3-blade cutter to match). It works surprisingly well, having accidentally tested it on a marina lazyline that got sucked into the propeller.
It requires a modified anode, which you can either buy for triple the price of the normal ones, or modify yourself (Zinc is soft and easy to work with hand tools and vise). Just buy once and then use as template for modifying your own.
The propeller also is modified with two holes for the rotating part to slot into.
The model of your saildrive is written on a nice label plate on top of the gearbox.