Getting better at pole vaulting from home

I've been into pole vaulting for about 3 years now and even though I'm really not good at the sport I just love it. I train 4 or 5 times a week and I feel I could do more on my own. The problem is that pole vaulting requires so much equipment and so I can't come up with exercises I can do on my own to help my jump. All I have is some light dumbells and a chin up bar. Apart from that all I can do is running. All I do now is an exercise in the bar that emulates the swing up from the jump. Any suggestions on exercises I can do?