Liberty Tree has the US Experimental M2 Hyde-Inland SMG Oiler on their Web site for $$20.00 also.
https://www.libertytreecollectors.co...idproduct=1386
Marcus sent me pictures of the Real I cut Oiler with a O on the cap and copies of the drawings, which was never implemented. But it's a awesome piece of Carbine development history.
I'd feel better about asking him, before I posted a picture.