Local hardware store for fittings and a low pressure gage.
Old tire valve stem, cut the rubber off and fit it in a hose.
Rubber expanding frost plug bung or a metal plate and rubber sheet to seal the exhaust.
Round plumbing plug to seal the intake where the carb fits on.
Cheap and easy to make, some members used to sell them on here.
Do a search and find past threads outlining how to make your own.
You need it.
Steve