Actually, the real thing can be seen (and played) at the Computer History Museum (CHM) in Mountain View/CA. [1][2] As far as I know, there's only one restored and functional PDP-1.

(There are some unrestored, like at the Smithsonian, but these are stored away in boxes.)

[1] https://computerhistory.org/exhibits/pdp-1/

[2] https://www.computerhistory.org/pdp-1/

Regarding the CRT tube and phosphor: The display uses a CRT tube developed for RADAR, which uses P7 phosphor. This features a short, responsive activation in bright blue and a long sustain in greenish-yellow. (It's actually a 3D display, as in X/Y and time. It also features 8 intensities of brightness, which do not scale too well, for which Spacewar! rather manages apparent brightness by refresh rates.)