Lyn, how mechanically inclined are you? If you are not, do you have a mechanic in the area you can trust? Also contact the previous owner (seller) and ask how long the light has been coming on. Try to get as much information as you can from him about the previous ownership, etc. That will help a ton and it's free, if he feels guilty and is convicted enough to tell you..

 

Stop right there. Go find a proper mechanic.

What you are describing as "my local mc" is apparently just an oil and filter change monkey.

 

Here is what you need...maybe.
Oil Pump Gear Kit | Land Rover Engine Parts at RoverParts.com

Do this first, go and have the oil changed, any place you want other than the dealer.
I repeat, DO NOT go to the dealer!!
Tell them you want them to use diesel oil, 15w-40, write it down so you do not forget.
Make sure you are using premium gas, this is a must as it is required by Land Rover.
Report back if your oil light still comes on or stays off at ENGINE IDLE.