91 Integra Where to get engine parts?

[91Intergra]

Aight guys, first time on this forum, I have a 91 integra LS to door hatch
b18a1 with 143000 miles, she was driven soft, but i drive it hard now that i got it.

Now i want to change my engine, or convert its ass to a b18c1 VTec, believe its a GSR motor, or if you guys have a better suggestion for a motor or even a conversion whichever will be cheapest, i dont want an extremely fast car as of yet,
im not racing or anything but i wouldn't mind like 160-170 horse.

If you guys could help me out on cost and where to get parts i would appreciate it much

p.s. i got damn power seat belts

Tim