Mini-spool on the street.

I would not use a mini-spool for the street. It could break parts, but mostly it will make it more difficult to drive in turns when the weather is bad. A locker would be a better choice, it is cheaper and easier than replacing the whole rear and it is safer than using a mini-spool. Some lockers are noisy in tight turns, but I am not able to hear mine over the exhaust so it was not a problem for me. I would imagine they are quieter in newer models now since I bought one about 5 years ago.

What type of locker would be best for a 7.5 10 Bolt? I know these arent very dependable but I am on a limited budget and cant afford to replace the entire rearend.

I used a Lock-Right Powertrax locker by Richmond, they make it for a 7.5, but I used it in an 8.5 corporate 10 bolt. I would use summit to see who else makes one for a 7.5 rear and select one from there. I am sure that Detroit Locker makes one for the 7.5 as well. In general they all should work about the same, although some will be quieter than others.