There aren't many PCIe sound cards; the cheapest is the Xonar DX, which
is slightly above this range when new, but has an excellent ADC.
USB devices tend to cost more than comparable cards, but there are
stereo recording interfaces where you don't have to pay for 7.1 outputs
or a Dolby Digital license. Such devices would be, e.g., the Behringer
UCA202 (which is cheap) or the Roland/Cakewalk UA-1G (which is not).
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