Hi Craig, the ones below are the ones I know though I only shopped at the last one - Citerne Maurice-Victor - which is close to Metro République in central Paris but is alas the only without website. Checking the others' websites below may give you a better view as to whether they've anything in store of interest to you without going there.

Boutique Auto Moto (Metro stop: Chatelet)
Address : 6 Rue des Halles
Phone : +33 1 45 08 05 05
Web Site : https://boutiqueautomoto.com/index.php
AJC miniatures (Metro stop : Maraîchers)
Address : 78 Rue des Pyrénées
Phone : +33 1 40 09 99 93
Web Site: https://www.ajcminiatures.com/

Dan Toys (Metro stops : Commerce, Felix Faure, Boucicaut)
Address : 115 Rue de la Croix Nivert
Phone : +33 1 56 08 09 57
Web Site: https://www.dan-toys.net/

Toute La Miniature Automobile (Metro Stop: 500m Porte de Vanves)
Address : 85 Bd Lefebvre
Phone : +33 1 42 50 41 62
Web site : https://autominiature75.com/autos/route

Citerne Maurice-Victor (Metro stops : République, Temple, Filles du Calvaires)
Address : 21 Bd du Temple
Phone : +33 1 42 78 00 16