Hi Shashidhar,
I was considering the OPA 2134-based preamps. They have found favour with many DIYers.
I have not come across the STK chip you mentioned. The common ones are the 4141 and 4171 power amp ICs. If I stumble upon them, I will inform you.
My address is Vivek Phadnis, 8/9, 4th Cross, MT Layout, 13th Cross, Malleswaram, Bangalore-560003.
I have an LM 381-based preamp circuit with bass and treble controls from Electronics For You. I could send it over if you want.
Regards,
Vivek