what is this and how much will it take to have it repaired?

From the sounds of it it sounds like a cam seal or something else. You may want to have this looked at by a garage or two, and get prices. It's hard to tell what you're referring to by your description alone.

cant really tell you due to lack of information but i recently had a oil leak on my 95 teggy different engine obviously but i had to get 2 cam seals, a crank seal, a timing belt, and a valve gasket cover all replaced totaled just under $700 i wasnt too happy

cam seal. b series is notorius for leaky cam seal

definitely a cam seal. i had that exact same problem on my 97 ls. its a very easy fix if you know a decent amount about the b series motor. all you gotta do is remove ur head and ur exhaust cam.

Lol 700 u could of ordered all that on eBay for maybe 70 butmorelikely 7 bucks