The absolute cheapest way, so long as electricity isnt super expensive, is just to leave them on the PC. You'll not really be able to achieve the same "feel" and print quality of the original book, and if the scan isn't particularly high rez, they'll look a bit rough on the printed page as opposed to the screen.

If you have *LOTS* of them, an alternative would be to get an e-book reader that's compatible with CBR (or RAR, as it's the same thing) files, or ZIP etc (converted from CBR). Unfortunately I haven't seen any that offer colour yet - is this a problem?

After that, you'd probably be best to look into getting a (colour) laser printer. Find out how much each model typically costs per page (in terms of paper and toner; it may be worthwhile adding, say, 25-50% onto this as you'll be using more toner than a typical business document does, and you might want to use special paper for the best feel-a-like effect), figure out how many pages you're going to print, and do the math with this vs the purchase price.
(If you were going for absolute bulk, take the lowest cost-per-page.. but you're not buying something here to do the same kind of volume that a workplace mono laser might have expected of it (I've had use of one that had clocked up nearly 300,000 pages - the purchase price is moot by that point, as a £600 one still only costs 0.2p/page, vs a more toner-hungry £300 one that's overall 0.1p/page but uses 0.5p more toner)…. you might be doing a few thousand pages at best (one big 5-ream box of paper = 2500 pages) before it becomes horrendously tedious, so aim for a good balance. Remember to check out if it includes typical paper costs, and any price for double sided prints if so.

Don't bother getting the expensive duplex (double sided print) option, just set the PC to print every odd page, then flip & reinsert the stack and print every even one. (Do a short one first of all to make sure you've got the method right). It's purely a convenience thing, and in some cases can be hellishly slow.

If you're doing quite small volumes, the "high" price of a laser might be too much, though they've come down quite a lot recently. Try a moderate priced inkjet instead (the cheap ones will have crappy output, and gouge you on ink costs). Again, do the math. This probably won't be practical for anything over a couple thousand pages, probably quite a lot less, maybe even just one or two reams.

And once you've done the math, compare it against just buying the things outright (even if you have to settle for re-issues). Home printing is pretty expensive all told, you may be surprised at the comparitive costs.

Don't bother going to a commercial print house though. If they even agree to touch the material (most won't, as it's copyrighted), it'll be damn expensive - they're offering a commercial service, not messing around.

EDIT - colour photocopying for bulk copies? Actually that too depends on the machine quite a bit … workplace I left a few months ago had just taken delivery of some new colour copiers for the central copy room that had, "finally", brought the effective cost of use down below that of both the workroom inkjet and mono laser printer… before that, we were under strict orders to only copy in colour when ab.so.lute.ly necessary as it was VERY dear in comparison to just dumping multiple copies out of the mono printer (which was about as efficient, and faster, than walking to the mono copier), and about as bad as the inkjet.
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Are they still under copyright? You will need the author's permission if you want multiple copies.
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