Today's surviving UNIVAC architecture is the first transistor-based machine, the 1107, which is not compatible with any of the previous designs that all used vacuum tubes. "Only 36 systems were sold."

https://en.wikipedia.org/wiki/UNIVAC_1100/2200_series

The 1108-II was the first SMP dual processor architecture that was sold commercially, announced in 1965.

The operating system launched on the 1107 is now known as OS 2200, and is still supported.

https://en.wikipedia.org/wiki/OS_2200

United Airlines remains a major customer for the UNIVAC architecture.

The first SMP Unix implementation was on UNIVAC hardware, and used the EXEC-8 kernel from OS2200 directly, implementing a Unix system call as a "shim" around it.

https://www.nokia.com/bell-labs/about/dennis-m-ritchie/other...

"The UNIX system for the UNIVAC 1100 series was built as an integrated development environment for transactions that run directly on EXEC. Unlike most other implementations, therefore, it runs not directly on the hardware but as a collection of user-level activities under control of EXEC. These obtain services that would normally be provided by device drivers, and some process creation and management services from EXEC. Any configuration supplied by Sperry, including multiprocessor ones, can run the UNIX system."