I would contact Jason at PA Racing ang Mark Tydo at Tydo Racecars. Both of them quoted me great prices (much better than the mailorder joints) when I bought my Ultracase. I've done business with Jason a couple of times and his service has been top notch.
In all fairness...they may have "regular" stuff, but they are known for custom low drag units. Pretty much standard equipment in Pro Stock cars...you could spend a couple grand on a ring and pinion if you wanted to.