Hello Peter,
Welcome to the Forum,
There are a couple of points that may your affect decision process.
Firstly, if you are buying from a business you will pay VAT, 20%. You are unlikely to recover this.
As Alphatds, and Vellfires, are Japanese Imports most, but not all, official Toyota Dealers will not work on them or supply parts!..
Consequently, it is wise to ensure that you have someone competent, if not yourself, to maintain it.
Getting an MOT will not be a problem, as any MOT station will be able to do that.
I have an 2006 MZ G Edition Alphie and feel sure it will last longer than I.
I paid a lot less than your budget and had a very classy conversion for a lot less too.
I don't have a pop top, but they will add a significant cost if yours has one.
Also, beware the height gain as that can prevent access to many car parks.
Have it checked thoroughly by the RAC or AA prior to purchase.
I hope this doesn't put you off Alphie ownership as it is very comfortable motoring.