oh boy. Get ready for an onslaught. You should consider a new suntour XCD or similar cassette hub with a wide range cassette. I am not sure what the BCD is on those older cranks but if they are 130 you can step down to a 39t chainring. If it's 144bcd 42 might also be the smallest.
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1 Super Record bike, 1 Nuovo Record bike, 1 Pista, 1 Road, 1 Cyclocross/Allrounder, 1 MTB, 1 Touring, 1 Fixed gear