Hi Rich.
Can't help you with your speedo issue I'm afraid but I can tell you you'll need to get the year of manufacture from Honda. They'll want the chassis and engine number and then Honda UK will apply to Honda Japan to get the details. That's what I had to do, can take a while as I'm told by my Honda mate the dept in this country is only small and deals with many cases. I seem to remember the fee was £30. Once you know the YOM you can get it MOT'd. You can get insurance on the chassis number for a limited time, you need that till you get the proper reg number.
Go to the DVLA fully prepared and you'll be laughing, the DVLA v55/5 form will give you a list of all you need.
Good luck
Eggsy.