With a zex kit your car could be a decently quick daily driver for $500.
IMPO performance has a 10 second single cam civic. That will cost a bit more than $500 .
For a gsr swap youre looking at $4000 and wont be much (if any) faster than a zex kit but will have potential to me much faster if budget allows.
check out www.jdmclub.com for engine prices.