Neither Leitz nor Carousel trays will fit this projector.
It works with the Sawyer's Rototrays or with the TDC straight tray.
The Rototray can be recognized as holding 100 slides, by having gear teeth on the circumference of the larger face, and not having any locking collar (the slides are held in the tray by friction).
The TDC trays are recognizable as being straight, and having no system to retain the slides (if you've taken the lid off, you'll have to be careful not to dump the slides). These trays are often called "Universal" trays, though they can't live up to that claim.
The bulb is FCS, very widely available, inexpensive and long-lasting.