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.
WWII BRITISH ARMY MODEL 1942 MK I DISPATCH RIDER HELMET ORIGINAL
$91.00 (9 Bids)
Time Remaining: 1h 29m
Original WWII British Brodie Steel Helmet in Desert Tan WW2 Dated Desert Rats
Time Remaining: 5d 21h 18m
Buy It Now for only: $79.95
Original WWII BRITISH HELMET NETTING Very Scarce Accessory Camoflauge Gift
Time Remaining: 20d 5h 53m
Buy It Now for only: $29.50
ORIGINAL WWII UNISSUED BRITISH HELMET 1941 1942 7 3 4
Time Remaining: 21d 21h 55m
Buy It Now for only: $139.99
WWII 1942 British Brodie Helmet With Liner and Strap
Time Remaining: 5d 1h 57m
Post WWII British MkIV helmet
Time Remaining: 5d 22h 26m
Buy It Now for only: $22.50
RARE British Army Firefighter LEATHER Helmet WWII BMB Briggs Motor Bodys FIRE
Time Remaining: 16d 11h 30m
Buy It Now for only: $149.65
Original British WWII Dated Brodie Helmet Waxed Camo Cover with Havelock
Time Remaining: 5d 21h 22m
Buy It Now for only: $84.95
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