Low cost DAC

Just got my Adcom gear back from cleaning and repair (GTP-500 preamp and GFA-555 amp). Source is an Onix XCD-88 CDP. Speakers (for now) are Pioneer SP-BS22-LR. in conversation with the repair guys, I asked if there was a way to run the audio from my Samsung 8500 Plasma (sources are Comcast cable box, Apple TV and PS3) through this audio system. They recommended a short toslink from the TV to a DAC to the preamp. They suggested a low-cost DAC from Amazon like the FiiO D3 or SMO Muse. Is there an alternative at or under $100 that would improve the sound noticeably both for TV and/or CD?