You say that you have taken out a loan for the Land Rover, was it a bank loan or car finance? I suspect that it was a bank loan, but if it was some other type of finance, particularly if the vehicle is some sort of security against the loan, you may have a legal way out.
Do not stick your head in the sand regarding the possibility that the Land Rover is stolen, it is not worth spending anything on it if it is knock-off as it doesn't belong to you and never will.
If it isn't stolen then you need to know for certain and if it is, the longer you leave it the harder it will be to get your money back off the vendor. as I said in my other post, you need to get a proper stolen vehicle examiner to look at it.
You don't list the other faults with the vehicle, but the loose drop arm that caused your steering issues is not a major issue, once it has been tightened up properly.
If you want to post some pics of your Land Rover we can give you some idea how old it really is, for example if the 300tdi is fitted way back in the engine bay and bolted to an LT77 gearbox (reverse up and to the left) then things would look more promising.