One other consideration: Assuming a 5-speed freewheel, 52-40/14-28 provides a superb 1.5-step gear ratio progression and was extremely popular in its day. 50-38 would take you down about as low as your rear derailleur can go, while still providing a great set of ratios, a reasonable top gear, and a very easy-to-find 5-speed freewheel.
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"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069