per Williams history Starr Revolvers and carbines were issued with Special Order 278 Dept of the Missouri in Dec 1862/Jan 1863. This matches the Starr .44 Cal Double Action contract period and matches the description well. See:
http://history-sites.com/cgi-bin/bbs53x/cwaemb/webbbs_config.pl?read=3402
and the following response http://history-sites.com/cgi-bin/bbs53x/cwaemb/webbbs_config.pl?read=3408
John R.