Hi Paul! I just purchased the 1:200 scale Trumpeter model to "display" in "my area". Quite honestly though, I decided to build the model myself to keep me in "my area" and out of the sight and sounds of the rest of the household (if ya know what I mean, wink, wink).
Whilst shopping for the best deal, I did run across a number of listings on both eBay and Amazon for prebuilt models, built out of a number of materials. Some are plastic kits, some were scratch-built wooden replicas. If I remember correctly, they were in the 1:350 - 1:750 range in size and averaged right around $250.00 USD. I would Google "Prebuilt Titanic Display Model" and see where that takes you.
Good Luck!