rear wheel about to collapse!

Was wondering why my newly-acquired '90 Townmate seemed a bit wobbly. Took the back wheel off today to replace the squared-off old tyre. While wrestling to release the innertube nut I noticed that one of the wheel spokes was floating in mid air at the hub end. Hmm, interesting, may as well check the other spokes... ah, that'll be another one completely unattached at the hub end. And another. Pinging the others, it feels like most of them are hanging on by willpower alone.   

So, assuming people don't re-lace wheels any more - anybody know where I can get a replacement wheel?

Found one thanks

Spokes for the Fs1e fit the townmate as do the wheel rims, so you can fix an old wheel. When I did my first one I cut out one spoke at a time and replaced it. By the time I was on the second one I did it in groups of four. Tention was achieved by first hand tightening each spoke then tightening each one a turn. Then checking that the wheel rotated true both up and down and left to right. Then tightening them in sequence, plucking each till they sounded right and about the same pitch. Not very scientific but seems to have worked.

Interesting info thanks, I'll keep the old wheel for spares anyway.