Yes I'd like to know which coil to buy. There are a million out there :-)
Here are some options, assuming you are still using the original distributor...which will be getting on in life.
BTW, it could be an additional or even alternate source of your problem. I find that ignition problems can spread among it components. https://www.roverparts.com/engine/ignition/RTC5628/https://rb.gy/cdlqthttps://www.roversnorth.com/parts/pli028_ignition_coil_3_5l_v8How do I check to see if I've got a ballast resistor?
A picture of the coil area is worth a 1000 words. OR, do you see an adjacent thingie like the one I am attaching below.
Your image posted to the Morgan Experience is too close in. Can you post one showing more area around the coil?
The consensus is I need a new coil. Mine is the original Lucas. Now I need to find one here in the US
It would be more correct to say that a failing coil is the FIRST choice of the cause. Lucas was the supplier of ignition and other electical parts in Morgans and other British cars. However, many other, often more reliable parts can be used to replace many of them. No one is going to offer an owner less money on a resale if their Morgan is more reliable.

gmg
![[Linked Image]](http://www.gomog.com/allmorgan/ballastresistor.jpg)