(Affiliate links ahead!)
A little birdie just told me about this stamping plate set from Huston Lowell...I haven't used it myself so I can't vouch for the quality, but word on the street (okay, in the Facebook groups) is that they pick up well, although the images are on the smaller side. So if your nails work with smaller images, you might want to check these out:
They're $14.99 for ten plates, and if you're a prime member, that includes shipping. Quite a deal!