Rereading the OP, I suppose that what Salvatore 123 says is true. I have some knowledge on obtaining original
PRINTINGS of the D/R Bible. I had a 1600 Antwerp edition of the Rhemes N.T. and currently have a 1633-1635 edition of the Cousturier Holy Bible. I have other original editions as well, and am still hunting for others.
First of all, Old Catholic Bibles are INCREDIBLY scarce!

That is simply because they were
illegal to own. Original D/R Catholic Bibles were also
VERY costly in their day. The original 1582 Rhemes N.T. was a lovely quarto printing, done in France, then exported (at personal peril) to England. It was virtually a death sentence to be caught with one of these Bibles at the time. There was a reprinting in 1600 in Antwerp of the N.T., again a lovely quarto edition, that was exported at great peril to England. They were often seized and burned when discovered. Further, since the printers had so little hope of profit from these Bibles, they were printed in very small numbers. In 1609-1610, the Douay Printing of the complete O.T. in 2 beautiful quarto volumes was FINALLY done. By this time, in the reign of James II, there was a little less rigorous enforcement of the penal laws. Consequently it is not as rare as the first two editions mentioned. However, today, those two volumes, even in fairly poor condition are valued at 5-10k dollars. In the 1620’s there was a small pocket sized D/R N.T. printed in Antwerp (I believe) that was not terribly expensive in its day, although I have never seen one for sale. Lastly in 1633-1635 the final printing of the full D/R was issued. This is also exceedingly scarce. You will find dozens -even hundreds- of original King James Bibles for every ONE original D/R bible.
Surprisingly, with the slim chance an original D/R had of surviving to our own day, some did, thanks to the great veneration with which they were cared for.
The best place to look for these Bibles is online, and through specialty auctions, especially the more high end type auction houses. Certain high end booksellers also are a good place to look.