I believe Freedom Arms also made them. I know someone who had one 10-15 years ago. I never shot it but that was several years before Magum Research introduced the BFR. As for that thing on Gunbroker, you couldn't pay me enough to shoot it. 45-70 is not the same bullet diameter as 45LC (.458 vs. .452) so even if it would shoot both the Colt would not even grip the rifleing.