Just some advice:
I used to do community work in this place called Heritage Conservation Centre (HCC). It's a place where NHB stores all their artefacts into this warehouse, and they specialise in doing conservation work for all the museum pieces in Singapore.
EDIT: It's near Jurong Port Road.
Not sure if they actually provide such services to the public, but hey, you may want to give it a try. But I gather that even if they provide such services, it may not be cheap.. with the treatments and all.
If you want to attempt doing conservation by yourself, you can get some of the materials that they use in the centre:
Acid-free paper-based products (boxes, sheets of paper blah blah)
Tyvek sheets - for cloth based materials I think.
Mylar sheets - for individual sheets I think, not sure if it works for a whole bundled newspaper.
The relative environmental humidity and temperature for conserving such items are important as well, and they vary according to the nature of the item archived. I forgot about the values for paper-based items, you may want to check with them.
Just my 2 cents.. hope I wasn't ranting.