TVR10K-E3/54 is an 800V diode from Vishay Semiconductor Diodes Division that has gone obsolete. 1N4947GP-E3/73GITB-ND from Vishay Semiconductor Diodes Division has been offered as a possible substitute. note* difference in speed replacement is faster.
To verify this part will work in your application or to view full specifications see the manufacturer datasheet. https://www.vishay.com/docs/88511/1n4942gp.pdf