The online retailers sometimes have entry level wheelsets with Shimano freehubs and decent rims for a good price. I got a set from Performance for $119 with 525 hubs and Rhynolite rims.
If the 3700 has a freewheel hub you might need to upgrade your rear shifter to an 8 or 9 speed and buy a cassette and new chain.
Or, you could just find the chrome moly steel solid axles that Niagara has and use one of those. It would still need periodic replacement. I personally feel a slight preload on the cone adjustment helps them last but some others seem to disagree.