There actually are already domestically produced coffees in America! And if other coffees end up forced to significantly raise costs, that would increase the market share and production of these coffees. It could end up being a major economic boon to places like Puerto Rico. The link I mentioned also covered non-domestic inputs, and not just final products. It's about 4.7%.
The lion's share of imports are going to be alcohol and purchasing produce outside of season.
It seems unlikely that we can grow enough coffee in Puerto Rico and Hawaii to make up for the difference. It might be good for those producers though.
Do you mean the lion's share of food imports or imports in general? Lots of seafood is processed elsewhere and imported the US. Strangely it appears ground beef is imported to the US even though we are a net exporter of beef.
The lion's share of imports are going to be alcohol and purchasing produce outside of season.