The RN's River class meets all those requirements except the last one. Given that new ones are being built as a BAE make-work project and the RN has no idea what to do with them, perhaps they would part with one of the Batch 1's at a bearable cost?
More realistically, the rumour that has floated around for the past year or so about leasing an offshore support vessel as a stop-gap replacement for the hydrographic and diving teams was presumably designed to address this hull shortage. Nothing has been heard for a while, so no idea if anything will come of it.
Our Royal Navy friends are at present selling or preparing to sell a number of vessels - including three batch 1 River Class (Severn de-comm'd last month and Clyde and Mersey going in 2019) and the research / hydrographic vessel the HMS Scott which has recently benefited from a MLR and will be gone by 2022. Also two MCM vessels Quorn and Atherstone are also going as is HMS Ocean, Bulwark and Albion, which the Brazilians are interested in and some Type 23's which the Chileans are looking at. Evidently the Ocean is offered for £80.3 million.
If you are an idealist, perfectionist and/or ship snob who thinks we can instant up a better quick fix for such modest money or throw money at it then - don't read the following.
Back in 2009 the UK MinDef bought the 5-6 year old leased Batch 1 Rivers for £39 million as a joblot. Each vessel costed around £5 million per annum to operate in RN service. All have had fairly recent refits - said to have 10-15 years of reliable life ahead of them. By all accounts they are not in a rubbish thrashed condition compared to the 20 year old early Leander Frigates - at least that kept us as a four frigate Navy for another 15 years - when we may have well been a 2 Frigate Navy by 1984 and a zero Frigate Navy by 2004!
Even with a further pre RNZN service refit/refresh these could well be a good opportunity at what would be fire-sale prices - we have a patrol capability gap as noted by the CN earlier this year - and three Batch 1 Rivers would effectively replace the limited and slightly younger IPV's and get us through to the 2030's when the current two Protectors are likely to be replaced - thus allowing a sequenced build of replacement OPV hulls.
The RN is retaining the Tyne in the interim as it is being used in the training role for the MCM squadron - which suggests one of the three for sale vessels could cover the Manawanui whilst the LOSC is in the pipeline.
Only the Clyde has a flight deck and no hanger, but one need not get hung up about that (think S100 as a work around) - nor have the IPV's and yes they would not be able to patrol south of Cambell Island - but the SOPV would and the two current 1C Ice Protectors would back that up. The B1 Rivers would be ideal for South Pacific, EEZ and northern sea lane approaches for patrol and presence work - and in comparison to the IPV's far greater utility for other roles such as maritime fire-fighting, disaster relief, anti-pollution work (think Rena), and the Severn and Mersey with their strengthen deck and 25 tonne crane able to embark and disembark light vehicles, palletised cargo, smaller TCU containers.
Three solid unspectacular EEZ workhorse's for probably half the price of one new build VARD 7 80-90m OPV like the Samuel Beckett Class for over a decade of useful work. With the SOPV we would then effectively have six OPV's rather than two OPV and four IPV's - and get a heck of a lot more capability without a dramatic increase in personnel numbers required or annual M22 output funding. When the HMS Tyne eventually comes available snap that up as a parts mule / alongside training / accommodation vessel.
Cheers, MrC
