Welcome to the forum George. I’m at the central NJ Shore.
As far as parts go, no MGTD Kit is currently in production. In fact, I only know of one company that produced a TD variant that is still in business, but they have been sold at least once and haven’t produced a TD replica for over 20 years. They have no parts left and I think their molds are gone too.
There is a place in Miami, FL that’s called MG Magic. They have a personal storehouse of MGTD replica kit parts and their inventory and price list is posted on another thread on this forum. They have no website, only a phone number, probably a basement and shed operation.
There are several British Sports car aftermarket suppliers that can provide some of the hardware (mirrors, handles, etc.), Moss Motors is one. Keep in mind that except for the British Coach Works TD replica, only one of these replica cars are true to the original TD shape or dimensions. Get your wallet out for this stuff too, it ain’t cheap.
The headlight buckets are a standard Hot Rod item and are probably available from a source like Speedway Motors, JEGS or Summit Racing.
If your front splash pan is split, you probably have a Classic Motor Carriages/FiberFab car.
So, if MG Magic can’t help you out and the part is not readily available, you are going to have to improvise.
I recently paid over $1,000 to have my bumpers, bumper overriders and grille shell re-chromed. The grille shells are no longer available, so this was the only route. When they were available from Moss Motors, they were well over $700 anyway.
As far as tops and side curtains go, keep the old ones for a pattern and get them made locally.
I guess your car is a front engine car? Is it a V6 or I4…sounds to me like you may have a Chevette based car, not one based on a Chevy Luv or S-10, but who knows? You need to send us some pictures so we can help you out.