Rycote do custom foam windshields - they may already have one. Just cover it with a special Windjammer for maximum protection.
The special design of the Rycote Windjammer minimises high frequency loss and maximises wind protection.
Does Rycote make a Windjammer that will fit over the 414's and their stock windscreens? I asked one of my local shops to do a search for me a year or so ago and they couldn't find any commercially-produced dead rat that fit the bill.
The Windjammers are not cheap. Lots of different sizes of Windjammers. And the one's that fit over the Rycote "baby ball gags" might work for 414's. I have 414's and can check for you.
I also have two 22mm Rycote Baby Ball Gags,
used once, which will be for sale and the Rycote windjammers for the baby ball gags will be for sale too. The 22mm baby ball gags are slightly too small for the Nevaton MK49s that I purchased them for.
http://www.rycote.com/products/baby_ball_gag/ 22 mm Baby Ball Gag Windshield
021801 - Baby Ball Gag Windjammer - Suitable for all sizes of Baby Ball Gag