A reasonably priced solution
My right-hand drive MG happens to have a side mount spare on the left-hand side secured by a black leather strap. it soon became clear that a left side mirror would be essential for safe operation on this side of the pond. A matching passenger side mirror to that mounted on the driver side door would have required drilling into the coachwork. A side mount spare mirror became the most obvious solution, which would also provide a better line of sight. The on-line photos of this product feature a black leather securing strap, which would have matched my existing leather side mount spare securing strap. The product was delivered with a light tan strap. This will need to be dyed or replaced to match the securing strap for my side mount spare. The supplied round mirror is nice quality but did not match the existing rectangular driver side door mirror. Fortunately, it is easily detachable and has been swapped for a matching rectangular mirror. I will save it for future use on another vehicle and even investigate obtaining a second mirror head in order to have a matching pair for future use.