Hi-Lux Optics currently offers three period-correct models that would be at home on a M1903A4 and the USMC M1903A1 sniper rifles.
Lockhart Tactical Raven Modular Semi-Auto Rifles - Hi-Lux Optics 6 X 3/4 Malcolm Telescopic Rifle scope 32 Long With Mount
M634321 Hi Lux Malcolm 6X Long Rifle Telescope - YRSInc
Wm. Malcolm Vintage Scopes
M1903 Springfield Rifles
Hi-Lux Optics Vintage Scopes - Guns and Ammo
Hi-Lux Precision Rifle Scopes and Optics
Hi-Lux Optics Vintage Scopes Guns And Ammo, 50% OFF
Hi-Lux Optics Vintage Scopes - Guns and Ammo
Hi-Lux Malcolm 20x Vintage Scope
Hi-lux vintage scopes
Wm. Malcolm 8X USMC Sniper Scope
Leatherwood/Hi-Lux Optics: 2012