Welcome.
I have literally this week finished my restoration of my Terrot MT1, 1950!
I came on here 'late' in the 10 month restoration as I needed advice on getting the engine to start. It has been a great help.
You are missing some parts, but try 'Terrot pieces' in ebay.fr and most of what you need is there and not too expensive.
A French company, Chambrier, are very good, but parts overall are very hard to find. (anywhere). They can make the exhaust tube and silencer to correct spec. The tube is a very strange diameter and not available in the UK.
I used BSA Bantam parts (handle bar levers), Universal cables off ebay, and Villiers Services for brake re-lining, chain, magneto magnetising etc.
CWS in Coleshill have the spokes, my rims were perfect. They have the correct sized tubes and tyres.
Getting it UK registered might be a bit frustrating, the VMCC club validated mine as experts on Terrots.
I found the bike to be well made, the carb awful and getting the engine to run miserable!
Good luck.
. I paid 2 x more for mine, and the total cost of the bike and parts/services has been £2400. Lost count of the hours...
I think there are 4 other MT1's in the UK, could be wrong.
This might help, the total restoration of my bike:
http://www.ddk-online.com/phpBB2/viewtopic.php?f=43&t=58463