Thought I would show the 2 cap badges I just received. Different lug mount as yours. The smaller one is silver marked. I assume it would have been a private purchase?
The smaller badge is a sweetheart pin. Note the hallmarks. The 4 CMR / 4 CMRR badges were made by at least two companies, Ellis (flat lugs) and Tiptaft (slider). There is a variety with only 4 CMR in the banner.
Are they all marked? I can't find a mark anywhere. I received mine with a medal set that belonged to Col. Sandford Fleming Smith, DSO, who help raise the 4th for WWI and later commanded the CLH