Companies that made American and Allied wing badges during WWII are listed below:

Note:  There may be more!! Also, many companies used multiple styles and marks. This is a general guide, not an exhaustive list.

Click to see sample (when available).

American companies, City, State and hall mark:

American Emblem Company 
Utica, NY  (A.E.Co.)
Fox ("F" in circle logo) Officer's Equipment Company
Madison, NJ (Officers)
American Insignia Company
New York, NY (AMICO)
General Merchandising Co.
Milford, Conn. (Gemsco NY)
Orber Manufacturing Co.
Providence, RI. (Orber, circle logo, sometimes defaced)
American Metal Crafts
Attleboro, Mass (Amcraft)
Goodwear Fabrics Co. Pasquale Uniform Company
San Francisco, CA. (Pasquale. S.F.)
Bailey, Banks & Biddle
Philadelphia, Pa (BB&B)
Hilborn-Hamburger Inc.
Passaic, NJ (H&H in eagle logo, sometime with Imperial)
Polar Flight
(Polar Flight)
L.G. Balfour Company
Attleboro, Mass (LGB, Balfour)
Imperial
Merged w/Hilborn-Hamburger (Imperial, sometime with H&H in eagle logo)
Robbins Company
Attleboro, Mass. (Robbins, "R" in wing logo)
Beverly Craft
Beverly Hills, Ca (palm tree logo)
Josten Inc
Princeton, Ill (Josten)
Starburst or "snow-flake" pattern. This is usually seen in pre-war insignia.

In particular in Amcraft used this pattern in its prewar wings and insignia.

Walter Lampl
New York and Mexico

This company most likely made the "Juarez" style wings. Wings are rarely found with the "WL" hallmark, more common are "Sterling" or "Coin Silver" hallmarks.

Tiffany & Company
New York, NY (Tiffany & Co)
V. H. Blackinton &Co
Attleboro, Mass (VHB, "Sterling by Blackinton")
LeVelle & Co
Philadelphia, PA 
Washington DC
(LeVelle & Co)
Vanguard Military Equipment
Long Island, NY (Vanguard)
Danecraft
New York, NY (Danecraft)
Luxenberg Uniform Company
New York, NY (Luxenberg)
Dieges and Clust
Denmark
New York, NY (Denmark)
N.S. Meyer
New York, NY (N.S. Meyer, Shield logo)
Charles Polk Company
New York, NY (CP Co NYC logo)
Dondero, Inc
Washington DC (Dondero)
Moody Brothers
Los Angeles, CA (Moody Brothers)
Whitehead & Hoag, Co.
Newark, NJ. (W & H in shield logo)
S.E. Eby
Philadelphia, PA (S.E. Eby)
Norsid
New York, NY (Norsid)
N.U.S. (US Navy wings only)

British companies:  

Firmin & Sons.
London, England (Firmin)
J. R. Gaunt Co
London, England (J. R. Gaunt)
Ludlow Co
London, England (Ludlow)

Australian companies:  

Angus & Coote
Sydney, Australia (Angus & Coote)
The Wallace Bishop Co.
Brisbane, Australia (Wallace Bishop Brisbane)
K.G. Luke
Melbourne, Australia (K.G. Luke MELB)
German companies:
Assman-Post war occupation