Thiel Owners

@blue222 - You're asking a lot.  I'm thinking your best bet is to buy a plain power amplifier and run your computer headphone out to it using RCA cables and an adapter.  

This and the comparable items are decent options I think.  Nuforce is supposed to be great for the money and is close to your price point.  The Dayton amp in the comparables below for 199 has been around forever so I think it must be a solid value.  For <300 I don't think you're going to find anything with fairly high power and decent sound.  Maybe if you go used.  I think you could find something that will be fine at low to moderate volume.  
https://www.amazon.com/NuForce-STA120-170watt-250watt-Stereo/dp/B010BJJ72Q

blue222

Welcome! Good to see you here.
Consider another Integra receiver, if you like its sound.

Otherwise, consider a Creek or Music Hall integrated amp.
This is a sonic match, especially, for a small room.

I look forward in reading more about your musical tastes and system.

Happy Listening!

Blue -  sometimes the least expensive route is to repair yours.

Tom & Beetlemania
Thank you for experimenting with the parallel speaker cable configuration ,  using Tom's finding I moved my cables
from 1 1/2" to 4"s ( as far apart as possible ) and heard or perceived a difference in front to back sound staging .
I repositioned my speakers to take advantage of the change .

Rob - you have stirred the soup. It's still cooking . . .