looking for a dac to connect my android tv box to an older analog amp. current analog out on the android box is really muddy and rubbish. looking at fiio d03k but is it still available? what other options do i have, not planning to spend.

Source: Himedia Q8 android box
Equipment: Luxman L2, Avid 100
Requirement: Output optical spdif from android box to be converted to analog for amp. mainly for music streaming and some light movies
Budget: Preferably under 300