you did not search very hard... but, you did not supply the country, therefore i do not know exact location of the site which can help you.
if you have board in your hand, check exact wording on the board and then try to search for it via google or any other search engine, try that one, one of my favourites:
https://duckduckgo.com/
try this guy, i bought from him before and he supplied toshiba power board exact model as i want, put in search box hisense and you will have several models, check for yours:
http://stores.ebay.com/shopjimmytvparts
this guys as well supply the parts, but i do not know how much they would charge for postage to your location:
http://hdtvparts.net/manufacturer/49-hisense-tv.aspx
by the way, this particular model was rather shiitty from the beginning, if you can change it for something else - do so... monitor/tv 32" new start from about $220.00, not long ago i did see in technip one on display (ex display with full w-ty) for $150.00... have look how much new ones look in your locality and then decide, maybe second hand online? try gumtree, craigslist or whatever you get in your locality, people move houses, interstate, they need to get rid of they stuff quickly...
hope this little advise will help you - do not forget to vote...