Not much to choose from
I was wondering how many casinos have Single deck PRESENTLY in Vegas?
The following downtown locations have dealer-dependent penetration, all are sweaty: Las Vegas Club, Golden Nugget, El Cortez, Western, Gold Spike (unplayable, only $50 table max). Four Queens has a single deck that uses a cut card, creating a nasty cut-card effect, making the game difficult to play. You will not be able to get much money on the table anywhere except LVC and GN, and those in short sessions only.
Others with one table each, all low-level grind joints: Fiesta Rancho (always crowded), Tuscany (worthless game 4 rounds heads-up), Fortune Club Henderson has Reno rules but not Reno penetration.
Current Blackjack News is the best source for this information.