Agreed you need new rims. Depending on the bike you least expensive route would be to head to your favorite local shop and just get a set of basic alloy 'off the shelf' wheels for around $100-120 I guess. hey should be able to just swap your freewheel to the new rear wheel and adjust your derailleur,
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk