Help finding Integrated Circuit

Thanks mate, I'll give your links a try and if I need more help from you I will let you know.

Cheers

From the description it's poweramp IC 18w there are quite a few found in NTE catalogue here: http://http://www.nteinc.com/specs/1800to1899/pdf/nte1879.pdf
Match pins or purchase an appropriate pin base if you need to re-fit it following the IC circuit diagram with pins here:
http://www.google.com/imgres?imgurl=http://radiomania.narod.ru/Sprav/chips/chips1/0286.gif&imgrefurl=http://radiomania.narod.ru/Sprav/chips/chips1/index.htm&h=480&w=640&sz=8&tbnid=c4QnL6HGGGPsDM:&tbnh=87&tbnw=116&prev=/search%3Fq%3DHA1350S%26tbm%3Disch%26tbo%3Du&zoom=1&q=HA1350S&usg=__UiPTWceura-pEBC0ljBkirUVlTw=&docid=KqgnHiyitvaW4M&sa=X&ei=8KCrUO6UEpKK0QGR8IGADA&ved=0CFQQ9QEwCA&dur=157

You can also find larger poweramp IC with same Vcc parameter and match the fittings if you want to use your creativity.
Let me know if you have any questions as you progress with project.