House Speaker Jim Wright (D-Tex.) said he is preparing a new package of non-lethal aid for the Nicaraguan Contras that will continue supplying them at current rates of about $1.8 million per month. However, he said other crucial questions remain unanswered. Among these are how the aid would be delivered, its duration and what kinds of incentives might be offered to Nicaragua's Marxist-led government to encourage compliance with a regional peace accord. The issue is scheduled for a House vote next week. Earlier this month, Congress defeated a $36.25-million package of military and non-military aid proposed by the Reagan Administration.