Hahaha!
Brexit costs calculated based on currency exchange rate trends not changing for two years!
Apart from that assumption being hilarious, perhaps not buying killtech would be a good option.
The Ministry of Defence is making £800m available for a Dragons' Den-style miltech startup funding panel – even as civil servants struggle to balance the books after the Brexit vote. The Royal United Services Institute think tank says that the MoD could face extra costs of up to £700m – which is based on the assumption that …
https://www.gov.uk/government/news/innovation-initiative-to-bring-future-tech-and-ideas-to-the-armed-forces
The 'VR Helmet' mentioned in the article is actually an AR (augmented reality) helmet for training exercises - infantry in a real field can see - and respond to - simulated tanks and aircaft etc.
One imagines that a competent future military command and special forces control would easily be able to ensure and assure and insure all necessary funding from whatever public and/or private body it chose to approach and/or terrify with its cutting edge, novel technology.
The current obvious impotence in that department of the MOD suggests there be both a catastrophic lack of commanding leadership and controlling intelligence in both the enlisted professional classical soldiering warrior type and sub contracting materiel supply personnel in the civil sector.
That does present a fantastic opportunity for players in such fields of endeavour though