It is undoubtedly a fine machine and I trust it is fun to ride but there is very little original Ariel in it and even less original trials Ariel, if indeed any at all.
Original Ariel bits are (probably standard roadster) crankcases, cylinder, head and rocker boxes. Timing cases also, but these are earlier than HT era ones. It is possible that the rear hub is Ariel, but not the brake plate or sprocket.
I assume the frame is a replica, along with the tank. Gearbox will be AJS / Matchless and goodness knows what the forks, wheels and primary cases are. Clearly, it is not possible to tell what the engine internals are, or what the clutch may be, but the ancillaries don't appear to have come from Selly Oak. The Ariel factory had closed by the time the Amal concentric was invented.
So, a great fun bike, but I am glad it is described as a "Trials" bike rather than an Ariel.
When I was AOMCC Machine Registrar, people used to ask me to certify that bikes like this one were Ariels so that they could get an age-related number from DVLA. I made myself very unpopular by refusing such requests.
36 4G, 37 VH, 53 ex ISDT KHA (project), 54 KH(A), Healey 1000/4 (project)
Former Machine Registrar & Archivist, General Secretary and Single Spares Organiser (over a 25 year period).
Now Archivist once more - but not Machine Registrar.