Thanks all for your efforts gotta love this place
Been in touch with hptyres - Dunlop no longer make the 235/605 R16 it was replaced with the 265 version.
Saw the link in the ROC as well thanks for the link
I have also been in touch with a race team who funnily enough run Radicals - they Have 22 in the garage at the moment
The well informed gentleman I spoke to said - the 265 will fit and would be nothing to worry about for track or sprint use, can't use them in the Radical series (not that I need to), when I asked why he said so Radical can sell more wheels
He can supply both wet and dry Dunlops, 1 race use and guarantee they will be good, more than fit for track and hill climb use, and they are a fraction of new cost and to top it all he has a set of the same wheels I have with a set of good slicks that he is willing to sell cheap as they are no good for series racing, he said buy the wheels get the tyres free - waiting for him to confirm prices.
So hopefully I now have a tire supplier and possibly a spare set of wheels so I can carry slicks and wets to track
But thanks again all that looked around for me