If you don't have an objection to a TWO TONE pistol..I don't....you can install a HUNTER trigger guard...about $120. You'll have to do some fitting also. Then you can sell your DRAGOON grip frame for $75 or more on one of the forums. I've converted several Original Size VAQUEROS with HUNTER grip frames and SUPER BLACKHAWK hammers. I like this set up as well as a BISLEY.
My latest Original Size VAQUERO is a 44 Magnum someone converted into a larger version of the 44 Special Sheriffs model. 3.5 inch barrel, total blue finish, and MAGNA-PORTED...the custom gunsmithing cost more than I paid for the gun! Now to round up a SBH hammer and a HUNTER grip frame for it.