I have been having a look at a little U Boat Drinkies uniform for after events and that it quite simple to put together
Apparently after Dunkirk there were so many british Battle dress blousen left behind that they kitted out all of the U boat crews with them. I was thinking of BD Blouse either a Olive Drab cotton shirt or white woolen jumper with cotton drill trousers and a nice side cap from some where like EPIC. Pop on a Lugar on you belt with an MP 40 and away you go. 
Agree not much scope for most games but you never know they may let a U Boat crew member on leave, fight the last line of defence game in a late war scenario
I think denims were most commonly used, rather than the wool.
You've got nothing to ein, zwei, drei, vier
and it would be the early war brown denims rather than the greens.
http://www.theuboatsociety.com/hermann/themen.html
beware annoying website music.
I did a drinking loadout using british denims, lots of naval bling and a cheap bundes white topped ratings cap with one of the drinking bling groups cufftitles as the tally.
I sold the denims on but still have the insignia, oh and a brown denim jacket somewhere if your interested?
Can have a look in the storeroom tomorrow if u want?
and it would be the early war brown denims rather than the greens.
http://www.theuboatsociety.com/hermann/themen.html
beware annoying website music.
MY mate sent me precisely that site about half an hour ago
Spearhead do some but no idea how good they are. TBH the pic doesn't look brilliant
http://cgi.ebay.co.uk/WW2-British-Army- ... 8198940905
might be worth checking that they are actually brown and not green.
Otherwise maybe try Steve Kiddle at Pegasus?
http://www.pegasusmilitaria.com/
expensive but awesomely good schmutter.
frankly a bit pointless for airsoft . You will probably get much easier advice on the pst forum. 
i believe there is a navy reenactor group about.
KM shore batteries were very common around the Atlantic wall. I'm just badging some denims for that very role. Just some detail differences from Heer [pointed boards and a gold eagle basically, there is more]but enough to be interesting.
Late war many thousands of sailors found themselves transferred to ground combat, some went straight in in their blues.
SoF/WPG were the two suppliers of early brown denims.
SoF have the later German made copy of U-boat denims off the peg so to speak.
Epic have caps, tallys and a reasonable range of badges with some look a like uniforms for not much cash..
aka Stigroadie
AFRA
better by design
"Truth is a shining goddess, always veiled, always distant, never wholly approachable, but worthy of all the devotion of which the human spirit is capable. "