does anyone knwo what flywheel and clutch and clutchbell will fit the o.s. .18cv-r 11j ? i'm going to get tthat engine but what parts will fit it? can i just buy any flywheel or any clutchbell for it to work in my hpi MT?

it depends on the car more than the engine. different gear ratios will give different results (bigger clutch bell = more top speed, less acceleration) the flywheel depends on what size the mt uses.