tyrie you ol ripoff merchant! I have a ramflo air filter assembly you can have since I have changed to ram tube and sock filters, I don't know if the ramflo filter assembly will fit the 45's though as mine are 40's.
But any how the offer is on the table all you need to pay is postage and it's yours
I actually have two kits for twin sidedraughts which may be useful if you want to go with twin sidies later on