Since these are too fragile for me to use without scanning them, I figured I might as well share. ;)
In general, Singer does provide copies of their old manuals. Some are available as free pdf downloads and many can be ordered (for relatively small fees) in a printed hard copy. If I don't have what you want, go check out Singer's manual section.
I'm not really a serious collector (I live in an apartment and already have too much stuff to collect many old machines), but I'll be happy to scan and upload original manuals for others. If you have a manual you'd like me to scan please email me and we can figure out timing and shipping. I'm not planning to charge money for this, you'll just need to pay postage to get the manual to (and back from if you want) my home. ;)
If there is enough demand I may eventually try to offer reprints of some of these manuals from Lulu. At the moment I don't have the time to handle the layout work and cleanup that the pages will need. Let me know if this is something you're interested in so I can gague general interest.