I've taken digital pictures of my work and the crispness is lost. The finite details, the grit of the paper or board that should show through, etc. Albeit, the professional scans I've had done don't match my works entirely once I take a look. But I can keep the orginals at hand at first look and bring the colors back to replicate the original. When that's done, all the other nuances show through as well . . . something that's lost with a picture.
Have you tried looking for a refurbished scanner? I wouldn't recommend Amazon for that, but a search through Google/Bing/Yahoo might bring something up. I like to look at the reviews on Amazon to judge what would be best. There is a grapic scanner by Epson that comes up with each search. It's pricey. An older model is availbe through some vendors, but when you try to order it, it's not in stock.
Good luck with your search.