RE: Parts needed for non surpass OS120fs HELP
You will have to ask in the general engines forum. We'd not have any parts for that engine. It was discontinued much too long ago. We don't know of any other engine's parts that will work.
You may also need to locate an engine that is otherwise worthless but has good rocker covers. Sometimes, you can locate a hobby retailer who sells to the engine collectors' market. They tend to advertise in small advertisements in the back of the model magazines. Auction sites and other model sites on the Web may be able to help you find what you need.