Paint recommendations and choices are absolutely, positively right next to religion and politics... Don't get offended or discouraged with the responses that you're about to receive...
First you must know if your painter will be using base/clear or single stage.
Second, if your paint supplier can't find a code, they aren't looking hard enough. Most paint colors will have variants. The term "exact match" will be relative. It may take some work to get your perceived "match" if you're the picky sort.
I sell Akzo Nobel paints where I work... Sikkens, Lesonal, U-Tech and a little known company called Wanda. We also sell private labeled primers and clears manufactured by Cumberland.
Most likely your painter will prefer or recommend base/clear.
Of the 3 base/clear urethane (color) brands that we carry, I mix Wanda colors by a HUGE margin over the other 2 higher priced brands for smaller shops and over the counter users... and complaints or issues are very far and few in between. The complaints that I do receive are usually a result of the painter cocktailing their own chemicals and not following manufacturer recommendations.
Unfortunately, you will most likely only be able to use what your painter recommends (read: stuff that he's used to using). They are usually (but not always) polarized to one method/brand or another.
Which brings us right back to my opening statement...