This bayonet is an original US Model 1905 or US Model 1942 that was arsenal shortened to reflect the changing philosophy of bayonet lengths and utility.

These bayonets have plastic grips, steel pommel, guard, and blade. The blades are the most notable in that the fuller or groove continues out the tip of the bayonet. On later examples - such as the first true M1 Garand Bayonet - the fuller will stop ~3" before reaching the tip.
There are several variants - spear-point (edges meet in the middle), saber-point (cutting-edge sweeps up to meet the back-edge), and the Bowie-point (back-edge is clipped as with a Bowie knife). This variant is the Bowie style. As can be noted, the most dominant feature is the clip-point of the Bowie-style blade; additionally, the single fuller is un-stopped (both sides).
Blades are have the typical markings according to their original model blades - US, serial number, arsenal, ordnance bomb, date, etc.

Scabbards are green "plastic" but more accurately classified as fiberglass; sheet-steel throat, US centered in ordnance bomb logo.

It is believed this variant bayonet was used in Pakistan as the blade closely resembles that used on British rifles sent there - such as on the British No. 9 Knife Bayonet .