Join Date: Mar 2011
Location: San Jose, CA
Bikes: 1980s and 1990s steel: CyclePro, Nishiki, Schwinn, SR, Trek........
late '70's to mid '80's Measuring the rear frame inside width (OLD for the hub) may give you a better idea.
Looks like a good project
If your team is not too heavy, and you are not planning heavy turning, tandem specific wheels are not needed.
* clean and inspect the current front hub; if no cracks, rebuild and re-use with new Wheelsmith or equivalent spokes.
* measure OLD for a replacement hub. Halo Spin Doctor is available in 135mm OLD for 48 spokes.
* Tektro R559 brakes; those center pulls are scary, even on a single.
* 700c rims; I'd go with Sun CR18 or Alex DM18; both relatively low cost.
Keep in mind that frame is no where near as stiff as a mid 90s or newer tandem.