replacement balance

I have a spiral tilt window balance that needs replacement. Here are the dimensions, 3/8" diam x 26" length: window is 34" ---> x 26 7/8" ^ weight is approx. 15 pounds. On the tubing JR either P or A is written on it, plus number 4. Could you recommend proper balance and tension tool,
and price? How can I get and order for 2 balances of recommendation and 1 tension tool. Image also enclosed.
Carl