I have no clue who makes them for snap on at this time and date but, (always a but) I do know what company still makes them in the USA, (at least for now).
SGS Pro Burs, they used to be made around the Cleveland, Ohio Area, tell you what they made a fantastic carbide burr set, but the cost even 30 plus years ago would break the bank, not sure about today's costs, plus no warranty to speak of. So, I can see why you would want snap on if they had a free replacement warranty should they break.
Wish I could have helped you out op.