If you don't want to gamble on cleaning, ebay and Amazon both have genuine VFR800 labeled injector sets, 4 for $185 or so. Brand new. And the ebay has what it claims are new injectors for $25 each to the US. I bet a similar deal that'll ship to the UK exists. Though I'm dubious that the $25 ones are genuinely OEM. Proper Honda branded ones are still to be had for $35-40 each.
Part number is 06164-PCA-000 -- it's the same for all applications including CRV.