You can get a brass replacement plug with a drain valve from Amazon for about $10. Once and done.
probably the worst thing you could do, useal the water heater that have nylong plugs are coated on the inside which is why they don't have anodes for plugs. this coating sometimes is applied to the start of the threaded area and by using a bras plug you could catch the coating and cause a crack that extends into the area not sealed by the plug. this would allow corosion of the shell to start. if you have a plastic plug stay with a plastic plug.
