Do you have any documented proof of these Mexican Silver Dollars being carried by Benjamin, Wood or Breckenridge.
When President Jefferson Davis was captured Wood used two twenty dollar gold pieces to buy his freedom. All indications were that they were carrying gold coin. Now they may have received change along the way in Mexican Silver but I do not think they carried very many Mexican Silver Dollars as they are very heavy.
Also Breckenridge when the troops were paid at Mrs. Moss' Home, he (Breckenridge said that most were paid in Mexican Silver Dollars. This too is questionable because the man that requisitioned the silver coin received only US Silver Coins from the Banks of Virginia. He traded gold and silver bars for the coin. No Mexican Silver Dollars involved.
Now the troops paid at "Jimtown, N.C." Jamestown, N.C. received about 5,000 Mexican Silver Dollars as they were carried from Danville, Va being a keg that John Hendren busted the head off in to make exchange in silver for CSA Paper Money. The citizens would not except the Mexican Silver and so they were carried to Greensboro and eventually to Jamestown, N.C. Each soldier and officer received about $1.17 as six men were paid seven dollars and they had to split the remaining dollar most gambled for the dollar instead of trying to find change.
At Charlotte, N.C. the soldiers and officers were again paid the same seven dollars for six men. Some soldiers here also received Mexican Silver Dollars. I know of one family in Walnut Cove that still has the Mexican Silver Dollar and the seventeen cents in change some of it being large pennies. Mexican Silver Dollars were plentiful during the Civil War as no one was minting anymore US silver dollars except the Philadelphia Mint. In New Orleans over 80 kegs of Mexican Silver was found there by General Butler of the CSA and it belonged to France and was exported to them. That is over ten tons of Mexican Silver Dollars. Also, the cotton trade mostly brought into this country Mexican Silver from Matamorus Mexico as cotton sales to Europe and England had dried up after 1862. So there are hundreds of reasons that Benjamin, Wood and Breckenridge could have ended up with Mexican Silver Dollars and they were not necessarily from the ones that were in the CSA Treasury Vaults in Richmond, Va.