The Revenue guidelines are very clear for a private import in that the car must be registered the next working day after its arrival in the State.
If I read the post correctly the UK dealer won't be sweating as the car has already been purchased.
I assume the OP is attempting to avoid paying VAT as the vehicle will be defined as a "new means of transport" and Irish VAT will therefore be due.
Extract from the Revenue site below. Covers it pretty well I think.
OP - depending on exactly where you are with the transaction you may be able to get a refund of UK VAT. Have a search and talk to the dealer.
SSE
When is VAT chargeable and payable?
New means of transport from other Member States of the EU
For VAT purposes a new means of transport is a goods or passenger vehicle that meets
either one of the two criteria following:
- It is a new means of transport if it is a motor vehicle or motor-cycle (other than a tractor) supplied six months or less after the date of its first entry into service.
- It is a new means of transport if it is a motor vehicle or motor-cycle (other than a tractor) that has travelled 6,000 kilometres or less.
If the vehicle meets
either of these criteria the vehicle is treated as a new means of transport for VAT purposes and VAT is chargeable at registration.
(Note: In this context "entry into service" means registration in another jurisdiction. If not previously registered the vehicle is new.)
Examples
Vehicle 5 months old with 8,000km - chargeable to VAT
Vehicle 7 months old with 5,000km - chargeable to VAT
Vehicle 7 months old with 8,000km - not chargeable to VAT
Note: The date of supply for VAT purposes is the date of sale of the vehicle if the vehicle is supplied at any stage within six months of the date of first entry into service.
Example: A new vehicle is first registered in the UK in January and an Irish resident then purchases the vehicle in May of the same year with the intention of registering the vehicle in the State in July. As this vehicle is supplied within six months of first registration i.e. May, VAT is liable in Ireland when the vehicle is registered in July.