It should never have been removed in the first place.
It would be better if this practice was regulated against, so that 'live' registrations stay with their original vehicles and 'dead' registrations, namely those off vehicles that have been officially scrapped, automatically go back in the DVLA pool and can then be purchased by people, at a capped fixed price (the same whatever the reg) or be reissued (relative to the year of the vehicle in question) to classics that come back into the UK.
Automatically putting dead registrations from scrapped cars into a DVLA run pool at a set price will also stop perfectly good cars being scrapped, so someone can get their hands on a particular registration.
The person concerned would have to pay twice, firstly the cost of said roadworthy vehicle (to scrap it for a much lower scrap value) and secondly to retrieve the reg from the DVLA, potentially making it a quite costly exercise.
Best wishes,
Mike.
1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
The price must be based on the number of searches 
but it is advertised on multiple sites.