Tronair - Cylinder Seal Kit | K-1035
Throwing out an entire item and starting anew is costly. Luckily that's not how reasonably minded individuals operate. If you are reasonable, invest in replacing parts.
The K-1035 is a cylinder seal kit that serves as a replacement for the Tronair 5 Ton Tripod Jack. It may work on similar units. To confirm, check the manual to your specific unit.