Umarex's Colt Peacemaker airgun features an all metal frame, fixed front sights, and a CO2 compartment in the grip.
Specifications:

Type	Air Pistol
Action	Revolver
Caliber	.177 Pellet
Capacity	6
Finish	Nickel
Barrel Length	5"
Sights	Fixed
Weight	2 lbs
Stock
OAL	11.25"
Scope	No
Magnification	N/A
Barrel Type
Velocity	380 fps
Power Type	CO2