Pistols made by the manufacturer of your item are known as "CZ's", and are invariably listed in all sources as such. CZ made at least four (4) small vest pocket-type autos in .25 cal. (6.35mm, in the European vernacular) and you are going to have to determine which model you have to get the proper magazine. To do that go to these websites, which have illustratrions of CZ pistols:
1. Go to Google and key in "Atlante Storico Delle Armi". Select the website (it comes up 1st on the listings when I Google it):
Atlante storico delle armi - Mar 1 -
Atlante delle armi corte - Immagini di 1450 pistole e revolver.
www.earmi.it/armi/atlas/atlas.htm - 92k - Cached - Similar pages
by clicking on the part of it. This will give you the website, translated in (poor) English. Click on whatever country of interest you have --- for you Czechoslavakia.
2. Go to www.littlegun.be and in the column at "Tchèque C.Z." click on the "E" and images of a whole bunch of CZ pistols will come up. Click on the images for endlargements.
Once identification has been made, go to www.e-gunparts.com/model.asp?idDept=56
Re-post here if they don't carry the magazines you need.