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The best ones were the mopar performance (P4876373) silicon hose but they are no longer available. Looks like mancini repops them. Well worth the extra money if you plan on keeping the car and driving often. The rubber ones always seem to swell up.
Pre '70 or '70 and later?
Pre '70 used a 3/4" (called 13/16 by some vendors) and '70 and up used a 1" bypass.
Either way, RockAuto (and just about everybody else) has got 'em.
Late: