Get the real deal- the period mono for cheap
At those prices, you could get a couple. Good chance it will sound more convincing than those reissues.
For sure tablejockey, the OP can get a much better selection and credits at Discogs.
For WSS please also consider the 2009 New Broadway Cast WSS tracks The original 1957 Bernstein Conducts WSS ain’t too shabby either. For covers I like 1996 Richie Cole Plays WSS, 1992 Bayless Meers Bernstein and 1997 Dave Grusin Presents WSS.
I personally would not pay for a mono. It was mastered in stereo and we had a stereo console during that "period."
My Original Broadway Cast CD is slightly Columbia Records trebly & compressed but it is spacious, 3d and clean. And oh yeah, I totally love the soundtrack of the recent Stephen Spielberg feature release. It's on Qobuz. Gustavo Dudamel gives Lenny (who's uncredited on my CD) a serious run for his money with the baton. Sound is multi-miked but done with panache. Fine singing. No shortage of drama or excitement.