Hi, you won't get "proper" hard disk-based hifi at that price I'm afraid. You would be looking upwards of £500 realistically.
The only way might be to get an iPod classic with a dock like the cambridge audio one, and one of the lifestyle systems recommended in the "reviews" section of this website.
You would then get the benefit of being able to use the ipod away from the system as well...
Teac dab300 it has a USB socket allowing the connection of a pen drive or much better an external USB small laptop type hardrive ,available in big sizes
Even though i have one though im not a 100% sure if it will play an ordinary music file ie you may have to convert to MP3/WMA first ,not tried a full uncompressed file , but converting will get u a lot more on the disc
Connect it up to tv and u get an onscreen menu of whats on the disc