Puerto Rico changed its gun law in December of 2019 to make carry permits
"shall issue" to all eligible applicants, rather than discretionary "may issue."
The fee has been standardized, whereas the old law allowed every
local jurisdiction to charge as much as they want, or not issue licenses at all.
And, according to the article in the NRA's official magazine,
Puerto Rico's new law allows for non-residents with a carry permit
from their home state to carry in Puerto Rico.
(That's not the same as "reciprocity" because apparently it doesn't matter
whether this other state that you're from will recognize and give effect
to a Puerto Rican handgun carry license.) Visitors to P.R. can carry their on their existing license from any U.S. state.