Hi and welcome to Just Answer. I'm sorry to hear about your TV. I will try my best to give you a precise and accurate answer.
The part number is XXXXX and is no longer available from the factory through any of my distributors. Your only chance would be to find a used one somewhere - quite risky.
I will say though, as someone who has answered this type of question probably 100 times, that the cost of a new panel will far exceed the cost of a new TV. You can probably get a brand new 55" LCD television for between $1000 and $1500. For comparison I looked at the cost of a 50 Samsung LCD panel and the cost is $2200!!! Add to that shipping and install.
There is one place that occasionally has used LCD panels: http://www.shopjimmy.com/ They do not have one for your TV at this time.
You can also try Vizparts at(NNN) NNN-NNNN.
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