British war helmets from WWII are little cheaper than those of WWI according to my research on all completed sales on eBay on the last 90 days. WWII helmets are traded every single day with minimum of 10 bids, which means there are great number of engaged buyers and sellers. You can expect to pay anywhere between $50 - $300 for a helmet based on condition & rarity.
If you are looking to buy a British helmet, you will have to join the bidding war. For example, on September 12, 2010, a WWII British helmet was sold for $267.88 with 24 bids. Take a look at the helmet on the right. It is not in great shape, but still goes for high price because of its rarity.
eBay is indeed the best place for searching WWII British helmets for sale from various sellers and collectors. I don't think there's any other place like it. Below are some of the listing from eBay. Browse the the listing and click on a link which you are interested in. You will be taken to a page with more information on the helmet.
Scarce WWII British Mk2 Camo Helmet
Time Remaining: 10h 37m
British WWII Paratrooper Steel Helmet
Time Remaining: 3d 7h 28m
Buy It Now for only: $94.95
SILVER SHOWA EMPEROR ENTHRONEMENT MEDAL JAPANESE HIROHITO ARMY RARE ANTIQUE WW2
$19.83 (8 Bids)
Time Remaining: 13h 44m
Original WWII British Brodie Steel Helmet in OD Green WW2 Dated
Time Remaining: 14d 18h 32m
Buy It Now for only: $79.95
JAPANESE FIREFIGHTER BADGE NAGANO JAPAN FIRE CHIEF POST WW2 FIREMAN VTG FD HAT
$31.00 (12 Bids)
Time Remaining: 14h 49m
WWII British Brodie Helmet Elastic Chinstrap 02
Time Remaining: 24d 9h 25m
Buy It Now for only: $19.95
Original WWII dated 1940 British Brodie Steel Helmet w insignia and strap
Time Remaining: 1d 4h 35m
Post WWII WW2 Danish British Shell Steel Military Helmet 1956
Time Remaining: 26d 13h 46m
Buy It Now for only: $59.95
Here is a list of previously sold British helmets on eBay. Use this as a guide so that you don't pay too much for a helmet in the future.
- Dispatch Rider Helmet 1945 - MINT : $200
- Paratrooper Helmet - REPRODUCTION : $157.50
- Tommy Helmet - 1942 - GOOD : $142.50
- Tommy Helmet - 1942 - GOOD : $79 (notice the difference in price. I checked the auctions and both are almost in same condition. If you shop, you can still buy the helmets for cheap)
- Motorcycle Helmet - 1945 - GOOD : $112.50