The M2 Tech Hiface provides excellent USB to SPDIF conversion. I have gone a different direction using the Toslink (headset outlet) out to a Pop Pulse that converts to SPDIF. Gives me great sounding 24/96 in the pre/pro. The Pop Pulse was about $150 - same as the Hiface unless you go for the modded version from John Kenny. His mods are well worth the investment IMO.
