Need parts shopping advise

I have an 8-1/4 rear with an open 2.45 gear. I'm looking to replace the carrier with a sure grip and 3.55. Where is a good place to shop for these parts. Summit's website gave me ONE gear option; 4.56! Dr. Diff has the carrier, but doesn't seem to sell ring and pinion sets. Richmond doesn't list prices, nor do they seem to sell direct. They ask you to type in your zip code and find a nearby distributor. Some others also had somewhat vague websites too. Can y'all help me out? What should I expect to pay for the carrier and gear set? It's going in a 1966 Barracuda with a mild 318 4speed street driven car under 300 H.P.

I just pulled a 7-14", Sure Grip axle (2.76:1) from my car. I have not had a chance to list it for sale. I have the driveshaft too. All brake hardware is brand new. Send me a PM if interested.