Have you tried Quinn Direct? They seem to be the cheapest for 'riskier' drivers?
I can't remember what the proposal forms for car insurance are like, do they ask 'have you ever been disqualified from driving?' or 'have you been disqualified within the last 5 years'?
To be honest I would advise you to bite the bullet, pay the €2k, and your premiums should start coming down in subsequent years (or has this not been the case in practice, i.e your premiums have not been decreasing?), if you keep out of trouble. Also, most companies allow you to pay 2 months upfront, and spread the remainder over 10 months (with a finance charge similar to those offered on personal loans), which might make the €2k slightly easier to swallow (it has done for me).
Another option might be to just get 3rd party (unless this is what you have been looking for already?)
Hope this helps.