As one who happens to like balls that are more core dominant rather than the standard weak core stronger covered lite oil and later games balls that most companies make---ok...I know it's a rare find but I will suggest a Track Flare...I have 2 of them drilled differently....the cover is weak by todays standards but the core has a .078 diff. For Something more findable, try a morich sahara, I have seen them pop up on ebay now and again. a strong assymetrical core on a relatively weaker cover.
Brad